ACUS48 KWNS 080927
SWOD48
SPC AC 080925

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0325 AM CST Mon Dec 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
Downstream of a prominent blocking high, which may be maintained
near/north of the Aleutians vicinity through this period, latest
medium-range output suggests that flow across the mid-latitude
Pacific through North America may trend less amplified by next
weekend into early next week. Relatedly, guidance is becoming more
unclear how impactful cold air, initially building to the lee of the Canadian/northern U.S. Rockies by late this week, will be in terms
of drying across the northern Gulf Basin, as it noses
south/southeastward in one or two surges through the remainder of
the period.

It now appears at least a bit more of a possibility that a weak to
modest elevated, if not boundary-layer based, Gulf moisture return
could occur on a developing southerly return flow, across parts of
the northwestern Gulf coast into southern Great Plains next weekend
into early next week. This could promote destabilization supportive
of a risk for thunderstorm development. However, with surface
cyclogenesis appearing unlikely to the lee of the southern Rockies,
the potential for severe weather appears low in the presence of
limited large-scale forcing for ascent and vertical shear.

..Kerr.. 12/08/2025

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ACUS48 KWNS 090929
SWOD48
SPC AC 090927

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0327 AM CST Tue Dec 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
Medium-range models indicate that at least a couple of short wave
troughs, digging within an initially strong northwesterly regime
across and to the east-southeast of the Canadian Rockies, will
contribute to reinforcement of large-scale troughing farther
downstream late this work week into next weekend. As this occurs,
cold surface ridging building to the lee of the Canadian and
northern U.S. Rockies is forecast to eventually overspread much of
the central and eastern U.S., offshore Atlantic and northwestern
Gulf Basin by the beginning of next week.

Based on the past few model runs, it appears that an initial
southeastward surge of cold air may weaken before reaching the Gulf
coast, allowing for a gradual boundary-layer modification over the
northwestern Gulf Basin to continue, before the more substantive
surge of cold air reaches the northern Gulf by late this weekend.
Particularly in association with the stronger front, if not also the
weaker initial one, a moistening elevated and perhaps boundary-layer
based return flow may contribute to sufficient destabilization to
support a risk for thunderstorms, anywhere in a corridor from
southeastern Texas toward the Mid South and Tennessee Valley.
However, with any surface frontal wave development forecast to
remain weak, the risk for severe weather is likely to remain low.

Into early next week, model output becomes more varied, but it
appears that flow may trend more zonal across the northern
mid-latitudes of North America. In lower latitudes, another
developing moist southerly return flow, in advance of troughing
digging across the southern Rockies and Great Plains, may contribute
to renewed thunderstorm development across the northwestern Gulf
coast vicinity. However, the potential for severe weather still
seems limited at this time.

..Kerr.. 12/09/2025

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ACUS48 KWNS 100915
SWOD48
SPC AC 100914

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0314 AM CST Wed Dec 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Based on the latest medium-range model output, a vigorous digging
short wave trough is likely to contribute to substantive mid-level
trough amplification once again across the Upper Midwest/Great Lakes
and Ohio Valley, into and across the Mid Atlantic Seaboard this
coming weekend. It appears that this may provide support for
significant cyclogenesis along a frontal zone across the
northwestern Atlantic, while a strongly confluent mid-level regime
in its wake supports the southeastward development of a large cold
surface ridge across most areas east of the Rockies, including the
offshore Atlantic and Gulf Basin by early next week.

Thereafter, into the middle of next week, mid-level flow may trend a
bit more zonal, at least across the northern mid-latitudes of North
America. However, there is notable spread evident within and among
the various model output concerning short waves emerging from the
upstream blocking pattern, before progressing inland within
splitting branches of westerlies across and east of the Rockies.
After an initial suppression of Gulf boundary-layer moistening early
next week, a developing southerly return flow with moistening that
may lead to increasing convective potential appears possible across
and northeast of the northwestern Gulf coast/lower Mississippi
Valley vicinity. The extent to which this could include a risk for
severe storms remains unclear, but currently still appears generally
low through at least this period.

..Kerr.. 12/10/2025

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ACUS48 KWNS 110929
SWOD48
SPC AC 110928

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0328 AM CST Thu Dec 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
Latest medium-range model output indicates that the amplified
trough, likely digging through the lower Great Lakes and Ohio Valley
at the outset of the period, will continue rapidly digging across
the U.S. Atlantic Seaboard, before pivoting offshore and supporting
strong cyclogenesis through the northwestern Atlantic into early
next week. In its wake, an initially expansive cold surface ridge,
centered near the mid/lower Missouri Valley, may gradually weaken,
but is forecast to continue southeastward into and across the
offshore Atlantic, Florida Peninsula and much of the northern Gulf
Basin.

Thereafter, it still appears that mid/upper flow may trend more
zonal, particularly across the northern U.S. and southern Canada,
downstream of a blocking high that is forecast to be maintained, but
become suppressed to the south of the Aleutians. Short wave
developments embedded within this regime remain uncertain, but there
is still at least some signal that a developing southerly return
flow may support a modest influx of moisture off the northwestern
Gulf by the middle of next week. This could contribute to
thunderstorm development across parts of the Mid South through
portions of the lower Ohio and Tennessee Valleys Wednesday into
Thursday, ahead of a modest cold front. However, at this time, it
appears that some combination of weak/limited destabilization and
modest shear/forcing for ascent will tend to minimize the risk for
severe storms.

..Kerr.. 12/11/2025

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ACUS48 KWNS 120921
SWOD48
SPC AC 120919

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0319 AM CST Fri Dec 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
Strong high pressure will dominate the eastern CONUS on Monday with
offshore flow across then entire Gulf Coast and East Coast. This
dry, continental polar airmass across the eastern CONUS will result
in no thunderstorms east of the Rockies on Monday and Tuesday. Some thunderstorms are possible along the coastal Pacific Northwest where
some weak instability may be present.

By the middle of next week, moisture return should resume across
Texas. This may result in some thunderstorm activity by early
Wednesday in the east Texas vicinity. Beyond Wednesday, model
uncertainty increases substantially. However, severe potential will
still remain too low as even the most favorable mid-long range
guidance indicates minimal instability and low severe weather
threat.

..Bentley.. 12/12/2025

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ACUS48 KWNS 130847
SWOD48
SPC AC 130846

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 AM CST Sat Dec 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
Moisture return will begin on Tuesday/D4 across Texas with some weak instability and thunderstorm potential arriving by Wednesday/D5.
Significant differences in the upper-level pattern begin on
Thursday/D6 and beyond which will significantly impact thunderstorm
and severe weather potential.

The ECMWF and AIFS have a sharper mid-level trough farther south on Thursday/D6. This will result in a stronger cold front and farther
north moisture return ahead of the front. In addition, some weak
instability may develop beneath the stronger mid-level jet. This may
create an environment favorable for a few stronger storms from the
Lower Ohio Valley to the Mid-Mississippi Valley. This stronger
scenario would likely push a strong cold front deep into the Gulf on
Friday and limit thunderstorm potential into the weekend.

A less amplified solution (as shown by the GFS and AIGFS) would not
support much of any strong storm threat on Thursday/D6. However, it
would keep low to mid 60s dewpoints across Texas and the Lower MS
Valley on Friday and into the weekend. This may result in weak to
potentially moderate instability across portions of the southern
Plains and possibly into the Mid-Mississippi Valley through the
weekend. Despite this lingering instability, a mostly zonal
mid-level pattern would not support a significant severe weather
threat.

Overall, severe weather potential remains somewhat low for much of
the period. Some low-end severe weather threat may exist from
Thursday/D6 and beyond as low-level moisture increases, but
significant uncertainties in the evolution of the upper-level
pattern make any forecast for time or location of any potential
low-end threat difficult.

..Bentley.. 12/13/2025

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ACUS48 KWNS 140958
SWOD48
SPC AC 140956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Sun Dec 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
Northward moisture return is expected to persist through the period
on D4/Wednesday as a strong surface low moves across the northern
Plains and Upper Midwest and strong southerly flow expands across
much of the warm sector. Despite the moisture advancing well inland,
warm air aloft should limit strong thunderstorm potential on
D4/Wednesday.

By D5/Thursday, weak to moderate instability is expected from East
Texas to the Mid-Mississippi Valley. Strong shear will be present
north of I-20 as a mid-level trough amplifies and a strong mid-level
jet overspreads the warm sector. Despite the presence of strong
shear and weak to moderate instability, updraft intensity may still
struggle due to weak lapse rates/warm air aloft. Only weak height
falls/cooling temperatures aloft are forecast south of the MO
Bootheel. Thunderstorms are likely from the Mid-Mississippi Valley
northward, where forcing will be stronger, but these regions will
remain well north of the more favorable instability. Therefore, any
severe weather threat would likely be marginal.

The cold front, associated with the storm system on D5/Thursday,
will move off the East Coast early on D6/Friday. Some marginal
severe weather may be possible Friday morning, but otherwise, severe
weather potential will be low as high pressure builds east of the MS
River in its wake.

By this weekend, return flow is anticipated across portions of the
southern Plains, but destabilization remains uncertain. A zonal
mid-level pattern with multiple embedded shortwave troughs is
currently forecast during that timeframe which commonly results in
considerably low predictability. Regardless of the exact outcome
over the weekend, there is general consensus for zonal flow and a
ridge building across the western CONUS and into the Plains. In
general, this will likely not support a significant severe weather
threat.

..Bentley.. 12/14/2025

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ACUS48 KWNS 150951
SWOD48
SPC AC 150949

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0349 AM CST Mon Dec 15 2025

Valid 181200Z - 231200Z

...DISCUSSION...
...D4/Thursday - Mid-Mississippi Valley and Lower Ohio Valley to the Southeast...
Isolated severe storms are possible on Thursday as moisture expands
northward ahead of a strong cold front. Forecast soundings show
strong shear across the region, but limited instability as 60+ F
dewpoints struggle to make it north of I-20. Given the strength of
the low-level jet, some damaging wind gusts are possible, but a
greater threat is not anticipated due to the aforementioned limited instability.

...D5/Friday - Carolinas to Georgia Coast...
Thunderstorms may be ongoing near the Carolina/Georgia coast on
Friday morning, but will quickly move into the Atlantic as a cold
front advances eastward. In addition, this front will move into the
Gulf and push rich moisture well offshore. As a result, thunderstorm
potential should be limited for the remainder of the D5 period.

...D6/Sat-D7/Sun - TN Valley into the Southeast...
Return flow will resume once again across the western Gulf over the
weekend. 60F dewpoints are expected to advect inland across East
Texas and Louisiana. This richer moisture may eventually interact
with a southeastward moving cold front at the end of D6 and into D7
with some thunderstorm potential. A few stronger storms may be
possible if sufficient instability can develop.

..Bentley.. 12/15/2025

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ACUS48 KWNS 160858
SWOD48
SPC AC 160856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 AM CST Tue Dec 16 2025

Valid 191200Z - 241200Z

...DISCUSSION...
A line of storms will likely be ongoing from portions of the
Northeast into the mid-Atlantic and Carolinas Friday morning. If
sufficient destabilization can occur, a few isolated damaging wind
gusts will be possible before the front moves offshore. In the wake
of this cold front, an extended period of low severe potential
begins. By Saturday afternoon, moisture is forecast to advect inland
across East Texas and Louisiana, but no thunderstorm activity is
expected. 60s dewpoints will remain along the Gulf Coast from Texas
to inland Louisiana and Mississippi through the weekend and into
early next week. However, building heights aloft will limit
thunderstorm potential for much of the extended. Even if some
thunderstorms occur early next week, as indicated by the 00Z ECMWF
across MS/TN, they will likely remain south of the stronger
mid-level flow and without strong destabilization, will be unlikely
to be severe.

..Bentley.. 12/16/2025

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ACUS48 KWNS 170958
SWOD48
SPC AC 170957

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CST Wed Dec 17 2025

Valid 201200Z - 251200Z

...DISCUSSION...
Southerly low-level flow will return to the southern Plains on
D4/Saturday. This will bring 60sF dewpoints to east Texas and much
of Louisiana with weak destabilization anticipated. A few storms may
be possible across Louisiana on Saturday night, but shear will be
weak. Minimal vertical shear combined with limited forcing and only
weak instability will preclude any severe weather threat.

Isolated thunderstorm activity is possible from D5/Sunday through
the first half of next week from East Texas and Louisiana into the
Ozarks and into the Midwest as slight enhancements of the low-level
jet promote isentropic ascent. Through this period, low to mid 60s
dewpoints will progressively advance farther inland. However,
instability should remain weak as mid-level heights build and
mid-level temperatures warm. Therefore, despite the inland moisture
early next week, severe weather potential remains low due to weak
instability, weak forcing, and building heights aloft.

..Bentley.. 12/17/2025

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ACUS48 KWNS 180904
SWOD48
SPC AC 180903

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0303 AM CST Thu Dec 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
An expansive area of high pressure will build across the eastern
CONUS on D4/Sunday and push a frontal zone near the Gulf Coast.
After this, ridging will build across the central CONUS and allow
rich moisture to advance well inland from the southern Plains to the
Midwest by D7/Wednesday. However, building heights aloft will result
in minimal if any forcing for thunderstorm development during this
period. Even beyond day 7, model guidance shows decent agreement in
a modest ridge breakdown without much severe weather concern.

..Bentley.. 12/18/2025

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ACUS48 KWNS 191002
SWOD48
SPC AC 191000

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CST Fri Dec 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
The large-scale mid-level flow pattern during the upcoming week will
feature ridging/anomalously high 500-mb heights over much of the
central U.S., and southwesterly flow with embedded disturbances
across the western states. Although low-level moisture will expand north/northeast from the southern Plains and Southeast into the
Midwest/OH Valley region during the week, instability will remain
generally limited due to warm mid-level temperatures. Overall, the
potential for organized severe storms is expected to remain low each
day.

..Bunting.. 12/19/2025

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ACUS48 KWNS 200838
SWOD48
SPC AC 200836

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0236 AM CST Sat Dec 20 2025

Valid 231200Z - 281200Z

...DISCUSSION...
The large-scale pattern next week will be highlighted by prominent
upper ridging and anomalously high 500-mb heights over much of the
central to eastern CONUS, with upper troughing developing toward the
West Coast by mid/late week. This pattern should considerably limit
deep convective potential over much of the CONUS, even while a
relatively warm/moist airmass will exist across the Plains and
Midwest.

With the approach of a low-latitude upper trough and increasing
moisture, thunderstorm potential, potentially including some
strong/locally severe storms with gusty winds, could occur across
coastal portions of central and southern California during the last
half of Wednesday/Day 5 into Thursday/Day 6 Christmas. However, the
degree of destabilization and some synoptic-related forecast details
remain uncertain.

..Guyer.. 12/20/2025

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ACUS48 KWNS 210921
SWOD48
SPC AC 210920

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0320 AM CST Sun Dec 21 2025

Valid 241200Z - 291200Z

...DISCUSSION...
Medium-range model guidance initially shows a pattern featuring an
upper ridge over the central CONUS and trough along the West Coast, transitioning to a more progressive flow regime and lowering heights
across the Great Plains during the Thursday-Saturday (D5-D7) period.
The inland-moving West Coast trough will potentially yield isolated
to scattered thunderstorms on Wednesday into early Thursday over
portions of southern and central CA and perhaps a localized risk for
a couple of stronger thunderstorms. Details concerning this
convective scenario and overall magnitude of severe risk preclude
severe highlights. Farther east, some moisture return northward
into the southern Great Plains and MS Valley through Friday will
likely be modulated by frontal advancements during the latter part
of extended period.

..Smith.. 12/21/2025

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ACUS48 KWNS 220927
SWOD48
SPC AC 220925

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0325 AM CST Mon Dec 22 2025

Valid 251200Z - 301200Z

...DISCUSSION...
An upper-air pattern featuring a ridge over the central states will
quickly transition to a more progressive flow regime towards early
this weekend. Model guidance implies a split-flow regime
potentially evolving with troughing over the Great Lakes towards the Sunday-Monday timeframe (D7-D8). Overall limited potential for
organized severe seemingly exists for much of the extended period.
Some indication for a moist sector evolving ahead of the amplifying
Great Lakes' trough could yield some severe risk, but predictability
is low and highly uncertain given model spread at this point in
time.

..Smith.. 12/22/2025

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ACUS48 KWNS 230943
SWOD48
SPC AC 230941

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CST Tue Dec 23 2025

Valid 261200Z - 311200Z

...DISCUSSION...
From Friday/Day 4 to Sunday/Day 6, a mid-level ridge is forecast to
move eastward from the central U.S. to the Eastern Seaboard. During
this time, a trough is forecast to develop in the Pacific Northwest,
and then to dig southeastward into the mid Mississippi Valley. An
associated cold front is forecast to move southeastward into the
Ohio and Tennessee Valleys by Sunday afternoon. Ahead of the front,
surface dewpoints in the 60s F should result in weak destabilization
with thunderstorm development possible along the front. However, the
models suggest that most of the convection will be post-frontal.
This limitation should keep any severe threat marginal.

On Monday/Day 7 and Tuesday/Day 8, the trough is forecast to move
across the eastern U.S. into the western Atlantic, with the front
moving off the Atlantic coast. In its wake, a relatively dry and
cool airmass will make thunderstorm development unlikely across most
of the nation.

..Broyles.. 12/23/2025

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ACUS48 KWNS 240943
SWOD48
SPC AC 240942

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CST Wed Dec 24 2025

Valid 271200Z - 011200Z

...DISCUSSION...
This weekend, a mid-level ridge will move from the mid Mississippi
Valley eastward to the Atlantic Seaboard, as a trough digs
southeastward into the north-central U.S. A moist airmass will
advect northeastward into the Ohio and Tennessee Valleys, ahead of a
cold front moving through the mid Mississippi Valley. Thunderstorm
development, mostly post-frontal in nature, will be possible Sunday
afternoon from the Arkansas River Valley northeastward into the Ohio
Valley. Although an isolated severe threat may develop, the storms
should be elevated and the threat will be limited by weak
instability. On Monday, the cold front is forecast to move to the
southern Atlantic Seaboard, with a dry and cool airmass residing
over much of the nation. This dry airmass is forecast to remain in
place through mid-week, keeping the chance for thunderstorms low
across the continental U.S.

..Broyles.. 12/24/2025

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ACUS48 KWNS 250948
SWOD48
SPC AC 250946

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0346 AM CST Thu Dec 25 2025

Valid 281200Z - 021200Z

...DISCUSSION...
A mid-level trough is forecast to move eastward across the central
U.S. on Sunday, as an associated cold front advances southeastward
into the Ozarks and mid Mississippi Valley. Near the front,
scattered thunderstorms are expected by afternoon from the
Ark-La-Tex northeastward into the lower Ohio Valley. Any severe
threat will likely remain marginal due to weak instability, and a
tendency for storms to be post-frontal.

From Monday to Thursday, the mid-level trough is forecast to
gradually move eastward across the central and eastern U.S.,
eventually reaching the western Atlantic by Thursday. In its wake, a
cool and dry airmass is forecast to overspread much of the
continental U.S., making conditions unfavorable for thunderstorms in
most areas.

..Broyles.. 12/25/2025

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ACUS48 KWNS 260855
SWOD48
SPC AC 260853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 AM CST Fri Dec 26 2025

Valid 291200Z - 031200Z

...DISCUSSION...
D4/Monday will feature conditionally favorable strong low to
mid-level flow along/ahead of a cold front moving east across the
Southeast. The intense eastern Great Lakes/southeast ON cyclone
should occlude as a secondary cyclone forms along coastal ME into
the Canadian Maritimes. Guidance is fairly consistent for this time
frame with indications of minimal instability along the trailing
portion of the cold front, as well as diminishing large-scale
ascent/convective signal through the day. Severe thunderstorm wind probabilities appear at or below 5 percent.

The continental airmass spreading across the Gulf in the wake of the
frontal passage should yield minimal severe potential mid-week.
Towards late week, return flow will support airmass modification
along the western Gulf Coast. The EC-AIFS hints at a low-amplitude
shortwave impulse in the D8/Friday time frame, which could support a
return to non-negligible severe potential.

..Grams.. 12/26/2025

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ACUS48 KWNS 270844
SWOD48
SPC AC 270842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0242 AM CST Sat Dec 27 2025

Valid 301200Z - 041200Z

...DISCUSSION...
A quiescent pattern is expected mid-week, in the wake of a D2-3
continental air mass intrusion across much of the Gulf. Return flow
and air mass modification will ensue late week into next weekend.
Run-to-run predictability remains low by this time frame, but some
models suggest a southern-stream shortwave trough could interact
with this moistening plume. This may support non-negligible severe
potential over the western Gulf States towards D8. Even this
scenario appears to be of sufficiently marginal amplitude, outside
of a singular 00Z CMC outlier, to likely yield low severe
probabilities through next Saturday. GEFS-based SPC-CSU and NSSL ML
guidance are in alignment with sub-5 percent severe probs on D8.

..Grams.. 12/27/2025

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ACUS48 KWNS 280840
SWOD48
SPC AC 280838

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0238 AM CST Sun Dec 28 2025

Valid 311200Z - 051200Z

...DISCUSSION...
Return flow will ensue along the western Gulf Coast mid-week,
yielding air mass modification from the prior continental intrusion.
Bulk of deterministic guidance has trended toward earlier EC-AIFS
signals of a low-amplitude shortwave trough progressing east across
the southern states through late week. While run-to-run
predictability and spread across models remains subpar, convective
potential should increase by D6-7/Friday-Saturday across parts of
the Gulf Coast States. At this point, with only modest cyclogenesis consistently progged, overall severe potential still appears
marginal. Latest ML guidance from SPC-CSU and NSSL for the GEFS, and yesterday's NCAR for the ECENS, support this notion with individual
day probabilities holding at 5 percent or less.

..Grams.. 12/28/2025

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ACUS48 KWNS 290912
SWOD48
SPC AC 290911

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0311 AM CST Mon Dec 29 2025

Valid 011200Z - 061200Z

...DISCUSSION...
Guidance consensus indicates a lower-amplitude shortwave trough will
approach the southern CA coast at 12Z Thursday. This feature appears increasingly likely to progress east across the southern states
through late week, initially inducing cyclogenesis over the southern
High Plains. This will aid in strengthening low-level moisture
return over the western Gulf, after a pervasive continental air mass
intrusion today.

Increasing convective potential is anticipated around late D5/Friday
to D6/Saturday across the Gulf Coast States from LA to north FL, and
into parts of the Deep South. Run-to-run-predictability and spread
across guidance remains less-than-ideal for timing/location of amplification/dampening details for this shortwave trough. Bulk of
signals are still for a modest surface cyclone and seemingly
lower-end severe risk. But there's enough minority signal to warrant
concern for a potential 15 percent area in later outlook cycles.

..Grams.. 12/29/2025

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ACUS48 KWNS 300848
SWOD48
SPC AC 300847

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0247 AM CST Tue Dec 30 2025

Valid 021200Z - 071200Z

...DISCUSSION...
A return of deep convection remains likely on D4-5/Friday-Saturday
across the Gulf Coast States from LA to north FL, and into the Deep
South. A low-amplitude shortwave impulse should emanate out of the
Southwest and may briefly amplify on D4/Friday over TX, as it
becomes absorbed within the broader cyclonic flow regime across
eastern North America. Latest guidance has decidedly trended towards
dampening this impulse and attendant surface cyclone reflection as
they progress across the Gulf Coast States/northern Gulf Friday
night into Saturday. This combined with predominately westerly
low-level wind profiles may support only a marginal severe threat.
After this minor wave, severe potential appears negligible in the
D6-8 time frame.

..Grams.. 12/30/2025

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ACUS48 KWNS 310953
SWOD48
SPC AC 310951

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CST Wed Dec 31 2025

Valid 031200Z - 081200Z

...DISCUSSION...
Primary severe concern will be across the northeast Gulf Coast
States, during the morning to afternoon on D4/Saturday. A
lower-amplitude shortwave trough remains consistently progged to
dampen as it progresses quickly across the Southeast and northeast
Gulf. With a weak surface cyclone, low-level winds should remain
veered. But this should be adequate for weak buoyancy to spread
east, emanating from the northwest Gulf and LA. With a more robust
convective signal closer to the coast compared to D3/Friday, at
least a level 1-MRGL risk should be warranted. This is supported by
latest SPC-CSU and NSSL GEFS-based ML guidance with overlapping 5
percent probability areas.

Along coastal CA, while run-to-run predictability is poor, latest
guidance has some signal for low-topped supercell potential this
weekend, downstream of a large-scale trough off the Pacific Coast.
This appears generally focused across northern CA on D4/Saturday,
shifting to southern CA on D5/Sunday. Spatiotemporal aspects of
individual shortwave impulses and attendant mid-level jetlets
relative to probable scant/meager buoyancy profiles will be crucial
for delineating areal highlights in shorter-term outlooks.

Otherwise, a combination of low potential/predictability remains
evident early next week.

..Grams.. 12/31/2025

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ACUS48 KWNS 010935
SWOD48
SPC AC 010933

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CST Thu Jan 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
Severe potential appears low through much of the period, with an
increase possible late next week. While run-to-run predictability
has been poor, latest guidance appears to be trending somewhat more consistently with the evolution of an upper trough off the West
Coast. This feature may evolve as a lower-latitude wave across Baja
CA and northern Mexico, or along the international border in the
Southwest States, before eventually emerging near TX. While
predictability is low for spatiotemporal aspects of this wave, it
may eventually interact with a modifying warm-moist sector from the
western Gulf into the South-Central States. SPC-CSU GEFS ML probs
highlight a 5 percent on D8/Thursday (although seemingly biased too
far north). Meanwhile, NSSL GEFS ML V1.2 probs highlight only a 2
percent on D8, but have a 10 percent on D9/Friday.

..Grams.. 01/01/2026

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ACUS48 KWNS 050951
SWOD48
SPC AC 050949

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0349 AM CST Mon Jan 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
The noticeable model differences on D3/Wednesday in the evolution of
a low-latitude shortwave impulse, ejecting ahead of an amplifying
upper trough over the West, persist into D4/Thursday. This renders
low confidence in a greater than low-probability severe risk on
Thursday, which appears roughly centered on the Ark-La-Tex to
Mid-South.

Peak severe potential still appears centered on D5/Friday.
Predictability remains sub-optimal with the basal portion of the
amplified upper trough from the Southwest. This renders large spread
across guidance in timing and amplitude of downstream cyclogenesis
from the south-central Great Plains towards the Great Lakes,
impacting the breadth of severe potential. However, with preceding
days of airmass modification from the western Gulf, a pronounced
wintertime warm-moist sector should become established towards the
Lower OH Valley vicinity. This should be coincident with a broad
swath of strong southwesterly mid-level flow that should be
strengthening during the period.

The trio of latest NCAR ECENS-based and SPC-CSU GEFS-based ML
probabilities have trended upward again with similarly large 15
percent regions. Meanwhile, the NSSL GEFS-based V1.2 has increased
back to a 10 percent, but displaced farther south. For this
forecast, have opted to include a 15 percent highlight, centered on
the Lower MS to Lower OH Valleys where confidence is greater for a
favorable convective environment on Friday afternoon to night
despite the modest synoptic-scale predictability.

ML probs for D6/Saturday remain low, with only the NCAR_Pangu
highlighting a 5 percent area. But given the aforementioned timing
differences with the evolution of the upper trough/surface
cyclogenesis, very fast deep-layer wind fields could persist atop a
more limited thermodynamic environment. A conditional convective
damaging wind threat seems apparent, with low confidence on spatial extent/amplitude at this time range.

..Grams.. 01/05/2026

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ACUS48 KWNS 061002
SWOD48
SPC AC 061000

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CST Tue Jan 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
...D4/Friday: Lower MS Valley vicinity...
A mid/upper-level shortwave trough initially over the southern
Rockies is forecast to take on a positive tilt as it moves eastward
on Friday, as a northern-stream shortwave trough digs from the
Canadian Prairies toward the Upper Great Lakes. Some guidance has
trended weaker and farther south with a surface low developing near
the lower MS Valley by Friday evening, though a relatively large
warm sector is still expected to be in place through most of the
period. Scattered to widespread storm development is expected from
parts of east TX into the lower MS Valley, with sufficient
deep-layer shear for organized convection and some attendant severe
threat. Some adjustments to the 15% area have been made, based on
guidance trends regarding surface low placement and the northward
extent of the favorable warm sector.

...D5/Saturday: Parts of the East...
Uncertainty regarding the synoptic pattern increases by D5/Saturday,
with varying solutions regarding the extent of mid/upper-level
trough amplification across the eastern CONUS, and the strength of
the related surface low. Guidance generally agrees that buoyancy
will be limited across much of the warm sector on Saturday. However,
any organized convection that develops Friday night may persist into
Saturday morning across parts of the Southeast, with some potential
for an isolated severe threat. Farther north, the strongest
solutions (such as the 00Z deterministic ECMWF) depict notable
intensification of low/midlevel flow from the Ohio Valley into the
Mid Atlantic, which could result in some damaging-wind potential
with any low-topped convection along or ahead of an advancing cold
front.

..Dean.. 01/06/2026

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ACUS48 KWNS 070917
SWOD48
SPC AC 070915

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0315 AM CST Wed Jan 07 2026

Valid 101200Z - 151200Z

...DISCUSSION...
...D4/Saturday...
Some severe potential remains evident from parts of the Southeast
into the Carolinas, Mid Atlantic, and possibly Ohio Valley on
D4/Saturday, but details remain uncertain.

Guidance generally depicts continued amplification of a deep and
progressive shortwave trough on Saturday across the eastern CONUS. A
deepening surface low is forecast to move from the Ohio Valley
toward the Lower Great Lakes, as a trailing cold front sweeps
through much of the Southeast and Mid Atlantic. Strongly sheared
convection with some severe potential may be ongoing Saturday
morning along/ahead of the cold front, from parts of MS/AL into the
southern Appalachians. Strong deep-layer flow/shear will eventually
overspread parts of the Ohio Valley, Mid Atlantic and Carolinas.
However, longevity and magnitude of the severe threat in these
regions is uncertain, as instability weakens with northeastward
extent, and stronger ascent becomes increasingly displaced north of
the warm sector with time.

...D5/Sunday - D8/Wednesday...
The cold front is forecast to move through coastal NC and the FL
Peninsula on Sunday, but weak ascent and buoyancy are expected to
limit organized storm potential. Dry and stable conditions in the
wake of this cold frontal passage are expected to minimize
severe-storm potential across the CONUS into early next week.

..Dean.. 01/07/2026

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ACUS48 KWNS 080918
SWOD48
SPC AC 080916

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0316 AM CST Thu Jan 08 2026

Valid 111200Z - 161200Z

...DISCUSSION...
Organized severe potential currently appears low through the
extended-range period.

A cold front will move through coastal NC and parts of FL on
D4/Sunday, in advance of a deep upper trough moving across the
eastern CONUS, but ascent and buoyancy within the remaining warm
sector appear too weak to support organized storms. For D5/Monday
through D8/Thursday, generally dry and stable conditions in the wake
of multiple frontal intrusions will tend to limit thunderstorm
potential across most of the CONUS. Some guidance (notably the 00Z
ECMWF) indicates that thunderstorm chances may return to parts of
the FL Peninsula by mid week, in association with renewed upper
trough amplification across the eastern CONUS. However, with
guidance generally depicting only weak surface wave development
during this time frame, confidence in organized storm development
remains low.

..Dean.. 01/08/2026

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ACUS48 KWNS 090945
SWOD48
SPC AC 090943

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0343 AM CST Fri Jan 09 2026

Valid 121200Z - 171200Z

...DISCUSSION...
Mid-level northwesterly flow is forecast to become established
across the central U.S. on Monday. This appears likely to persist
into mid-week as a large-scale trough develops in the Mississippi
Valley. The pattern will help to usher cold and dry air southward
into the Great Plains and Southeast, which will limit moisture
return. From Thursday into Friday, the trough is forecast to move
into the eastern U.S., reinforcing northwesterly mid-level flow over
much of the nation. As a result, a cold and dry airmass is expected
to remain over the continental U.S, minimizing the potential for
thunderstorm development.

..Broyles.. 01/09/2026

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ACUS48 KWNS 100941
SWOD48
SPC AC 100940

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0340 AM CST Sat Jan 10 2026

Valid 131200Z - 181200Z

...DISCUSSION...
A large-scale upper-level trough is forecast to develop across the
central and eastern U.S. during the mid-week. This feature is
forecast to move eastward toward the Atlantic Seaboard late in the
week, as another trough takes its place further west across the
Mississippi Valley. In response to the pattern, a large area of high
pressure is forecast to settle into the central U.S. on Wednesday
and move slowly across the Gulf Coast region on Thursday and Friday.
Another large area of high pressure is forecast to move southward
into the western and central U.S. by the weekend. As a result, the
airmass across most of the continental U.S. during the mid to late
week should be cold and relatively dry, suggesting thunderstorm
development will be unlikely during the Day 4 to 8 period.

..Broyles.. 01/10/2026

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ACUS48 KWNS 110947
SWOD48
SPC AC 110946

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0346 AM CST Sun Jan 11 2026

Valid 141200Z - 191200Z

...DISCUSSION...
A persistent large-scale upper-level trough is forecast to remain in
the eastern U.S. during the Day 4 to 8 period. This pattern will be
favorable for repeated cold air intrusions into the lower
forty-eight states from mid to late week. Cold and dry surface high
pressure will dominate across much of the nation, making conditions
unfavorable for thunderstorm development.

..Broyles.. 01/11/2026

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ACUS48 KWNS 120939
SWOD48
SPC AC 120938

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CST Mon Jan 12 2026

Valid 151200Z - 201200Z

...DISCUSSION...
A persistent large-scale upper-level trough is forecast to remain
over the east-central U.S. during the Day 4 to 8 period. This
pattern will be favorable for repeated cold air intrusions into the
continental U.S late this week into early next week. As a result,
cool and dry conditions are expected to remain in place over much of
the nation, making thunderstorm development unlikely in most areas.
No severe threat is forecast to develop over the continental U.S.
through early next week.

..Broyles.. 01/12/2026

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ACUS48 KWNS 120955
SWOD48
SPC AC 120954

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0354 AM CST Mon Jan 12 2026

Valid 151200Z - 201200Z

...DISCUSSION...
A persistent large-scale upper-level trough is forecast to remain
over the east-central U.S. during the Day 4 to 8 period. This
pattern will be favorable for repeated cold air intrusions into the
continental U.S late this week into early next week. As a result,
cool and dry conditions are expected to remain in place over much of
the nation, making thunderstorm development unlikely in most areas.
No severe threat is forecast to develop over the continental U.S.
through early next week.

..Broyles.. 01/12/2026

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ACUS48 KWNS 130937
SWOD48
SPC AC 130935

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0335 AM CST Tue Jan 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
A persistent eastern U.S large-scale upper-level trough is forecast
to remain in place through the Day 4 to 8 period. As a result,
northwesterly mid-level flow is forecast over much of the
continental U.S. In response, multiple cold air intrusions are
expected to take place across the central and eastern U.S. This will
keep a relatively dry and cold airmass over much of the nation
through early next week. For this reason, conditions will be
unfavorable for thunderstorms in most areas, and a severe threat is
not forecast in the Day 4 to 8 period.

..Broyles.. 01/13/2026

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ACUS48 KWNS 140931
SWOD48
SPC AC 140930

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CST Wed Jan 14 2026

Valid 171200Z - 221200Z

...DISCUSSION...
Medium-range guidance generally indicates that amplified mid-level
troughing, evolving by late week to the east of the Rockies, will be
maintained through this coming weekend, before a fairly prominent
ridge near and offshore of the Pacific Northwest/British Columbia
coast weakens and redevelops to the west/northwest. However, even
as flow trends less amplified, it appears that a broadly confluent
westerly to northwesterly regime to the east of the Rockies may
continue to support a series of southeastward developing cold
surface ridges. Toward the middle of next week, this may become
less of an influence across the southwestern into western Gulf
Basin, beneath a belt of strengthening mid/upper westerlies
emanating from the subtropical eastern Pacific. It is possible that
low-level moistening and forcing for ascent could become supportive
of sufficient destabilization for thunderstorm development by
Tuesday/Wednesday across the northwestern Gulf. However, it is not
yet clear that this will impact areas inland of the Gulf coast, or
become particularly strong.

..Kerr.. 01/14/2026

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ACUS48 KWNS 150949
SWOD48
SPC AC 150947

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CST Thu Jan 15 2026

Valid 181200Z - 231200Z

...DISCUSSION...
Medium-range models continue to indicate that highly amplified
mid-level troughing will persist across much of North America (to
the east of the Rockies) and the Gulf Basin through this coming
weekend into early next week, when an initially prominent ridge near
the British Columbia/Pacific Northwest coast begins to weaken and
perhaps redevelop to the west/northwest. Thereafter, sizable spread
remains evident within and among the various model output concerning
shorter wavelength developments and blocking within the larger-scale
split flow across the mid-latitude eastern Pacific, and the impacts
on the downstream flow remain unclear.

In general, it still appears that the Gulf Coast states and Gulf
Basin may come under the increasing influence of a strengthening
belt of westerlies emanating from the subtropical eastern Pacific,
and troughing may tend to dig within the mid-latitude westerlies
near and inland of the Pacific coast through mid to late next week.
However, even with guidance indicating potential for modest surface cyclogenesis to the lee of the southern Rockies by the end of the
period, it does not appear that moist return flow off a modifying
Gulf boundary-layer will yet become supportive of appreciable inland destabilization.

..Kerr.. 01/15/2026

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ACUS48 KWNS 160826
SWOD48
SPC AC 160825

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 AM CST Fri Jan 16 2026

Valid 191200Z - 241200Z

...DISCUSSION...
Broad upper troughing will persist across much of the CONUS from the
Rockies to the Eastern Seaboard during the Day 4-8 period. Surface
high pressure will largely keep Gulf moisture well offshore, with
cold air intrusions into the Plains and eastern U.S. precluding much
in the way of thunderstorm potential.

The exception may be briefly on Day 6/Wednesday across portions of
the Texas Coastal Plain vicinity. As a reinforcing shortwave upper
trough ejects across the Rockies, lee surface low development over
western TX will allow for very modest Gulf moisture to filter into south/southeast TX. A cold front will sweep south/southeast during
the evening/overnight and isolated thunderstorms could develop.
Severe potential appears low given modest moisture/limited
destabilization.

..Leitman.. 01/16/2026

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ACUS48 KWNS 160836
SWOD48
SPC AC 160834

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0234 AM CST Fri Jan 16 2026

Valid 191200Z - 241200Z

...DISCUSSION...
Broad upper troughing will persist across much of the CONUS from the
Rockies to the Eastern Seaboard during the Day 4-8 period. Surface
high pressure will largely keep Gulf moisture well offshore, with
cold air intrusions into the Plains and eastern U.S. precluding much
in the way of thunderstorm potential.

The exception may be briefly on Day 6/Wednesday across portions of
the Texas Coastal Plain vicinity. As a reinforcing shortwave upper
trough ejects across the Rockies, lee surface low development over
western TX will allow for very modest Gulf moisture to filter into south/southeast TX. A cold front will sweep south/southeast during
the evening/overnight and isolated thunderstorms could develop.
Severe potential appears low given modest moisture/limited
destabilization.

..Leitman.. 01/16/2026

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ACUS48 KWNS 170856
SWOD48
SPC AC 170855

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 AM CST Sat Jan 17 2026

Valid 201200Z - 251200Z

...DISCUSSION...
Convective potential will remain low for most of the CONUS during
the Day 4-8 period as persistent troughing envelops much of the
country. However, a couple chances for thunderstorm activity may
develop from TX to the Lower MS Valley vicinity on Day 5/Wed and
possibly toward the end of the period heading into the weekend.
These chances will occur as modified Gulf moisture impinges on the
TX coastal vicinity on Wednesday as an upper trough moves across the
Plains toward the MS Valley. Moisture return, in response to a
developing low in the lee of the southern Rockies, will remain
shallow, but could be sufficient for isolated thunderstorms across
portions of southeast TX into LA Wednesday afternoon into early
Thursday morning.

Some guidance suggests a weak upper shortwave trough and enhanced
southwesterly flow could overspread the Gulf Basin during the
weekend, bringing some deeper boundary layer moisture into portions
of the western and central Gulf coast states. However, guidance
varies considerably and run-to-run consistency is poor.

..Leitman.. 01/17/2026

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ACUS48 KWNS 180847
SWOD48
SPC AC 180845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0245 AM CST Sun Jan 18 2026

Valid 211200Z - 261200Z

...DISCUSSION...
A large-scale upper trough will develop eastward across the Plains
and eastern U.S. on Days 4-5/Wed-Thu. As this occurs, some modest
Gulf moisture will spread across east TX toward the Lower MS Valley
ahead of a cold front. Some low potential for thunderstorms will be
possible, but the modest moisture return will limit instability and
severe potential is low.

Beyond Day 5/Thu, forecast guidance is not in very good agreement
with large spread resulting in greater than normal uncertainty. The
control member of the ECMWF appears to be an outlier, showing some
increasing severe potential across the Gulf Coast states toward the
end of the forecast period. However, the GFS and EC-AIFS keep any
Gulf moisture offshore, precluding severe potential. Given these
large model discrepancies, severe probabilities seem low for now.

..Leitman.. 01/18/2026

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ACUS48 KWNS 190932
SWOD48
SPC AC 190931

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CST Mon Jan 19 2026

Valid 221200Z - 271200Z

...DISCUSSION...
Severe potential is expected to be low during the Day 4-8 period.
Some modest Gulf moisture will impinge on the coastal regions from
TX into MS/AL/FL beginning Day 4/Thu. Warm advection will allow for
showers and perhaps isolated thunderstorms, but weak forcing for
ascent and only very minor instability will preclude severe
potential. By Day 5-6/Fri-Sat, a deepening upper trough over the
western U.S. will develop east across portions of the Plains and
Midwest. A strong arctic cold front will move across the middle of
the country, ushering in another punch of cold to very cold air and
once again shunting Gulf moisture offshore. Some thunderstorm
activity could occur ahead of this front across the Gulf coast
states, but deeper moisture return is not expected and will be
insufficient for severe storms. Surface high pressure and a
cold/stable airmass will persist over much of the CONUS behind the
arctic cold front on Days 7-8/Sun-Mon.

..Leitman.. 01/19/2026

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ACUS48 KWNS 200853
SWOD48
SPC AC 200852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0252 AM CST Tue Jan 20 2026

Valid 231200Z - 281200Z

...DISCUSSION...
An arctic airmass will settle across much of the CONUS east of the
Rockies on Days 4-5/Fri-Sat. Resulting strong high pressure and
cold/dry/stable conditions will persist over much of the country
throughout the period. However, some thunderstorm potential could
develop across portions of the Gulf Coast states/Southeast on Days
4-6/Fri-Sun as a surface cold front progresses east/southeast.
Modified Gulf moisture will be in place near the immediate Gulf
Coast. Warm advection in the low-levels could result in isolated
thunderstorms near or just to the cool side of the cold front Friday
afternoon across parts of TX, spreading east/northeast across the
Southeast through Saturday and early Sunday. Instability should
remain weak as better moisture remains offshore, and due to
convection becoming undercut by the cold front.

..Leitman.. 01/20/2026

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ACUS48 KWNS 210837
SWOD48
SPC AC 210835

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0235 AM CST Wed Jan 21 2026

Valid 241200Z - 291200Z

...DISCUSSION...
A large-scale upper trough will shift from the Rockies through the
central and eastern CONUS Days 4-6/Sat-Mon. As this occurs, a very
cold airmass will overspread much of the country, with a swath of
winter precipitation expected to spread from the southern Plains
through the Mid-Atlantic. At the surface, model guidance varies, but
a deepening low is expected to develop over the central Gulf Coast
vicinity on Saturday night/early Sunday. The low and trailing cold
front will move offshore the Atlantic coast by early Monday.
Depending how far north the surface low develops, some thunderstorm
potential could increase across parts of the central Gulf Coast and
the FL Panhandle on Sunday. However, severe storms appear unlikely.
The very cold airmass settling over much of the country during the
weekend is likely to persist into early next week, precluding
thunderstorm potential through the end of the period.

..Leitman.. 01/21/2026

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ACUS48 KWNS 220856
SWOD48
SPC AC 220855

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 AM CST Thu Jan 22 2026

Valid 251200Z - 301200Z

...DISCUSSION...
A surface low over the Deep South on Day 4/Sunday morning will
develop east/northeast through early Monday, moving offshore the
Carolinas coast. As this occurs, an arctic cold front will continue
to push southeast across the Southeast U.S. Ahead of the front,
modified Gulf moisture will be in place, supporting weak
instability. As an upper trough approaches, large-scale ascent and
warm advection atop the surface front will support isolated
thunderstorms across southern MS/AL into northern FL and southern
GA. Modest instability and poor lapse rates should limit severe
potential within the warm sector.

By Day 5/Monday, the cold front will have moved well offshore the
Gulf and Atlantic coasts and an arctic airmass will envelop much of
the CONUS. Mean troughing is forecast to persist, allowing
reinforcing shots of colder air to filter southward east of the
Rockies and preclude any return flow across the Gulf basin.

..Leitman.. 01/22/2026

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ACUS48 KWNS 230955
SWOD48
SPC AC 230953

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CST Fri Jan 23 2026

Valid 261200Z - 311200Z

...DISCUSSION...
Amplified mid-level flow will persist over the US through next week
with troughing generally over the East and a building ridge to the
West. This will favor continued northwesterly flow aloft and
reinforcement of an extensive cold air outbreak and Arctic high
pressure over the lower 48. With little to no inland moisture
transport expected over the next week, severe weather is unlikely.

..Lyons.. 01/23/2026

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ACUS48 KWNS 240957
SWOD48
SPC AC 240956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Sat Jan 24 2026

Valid 271200Z - 011200Z

...DISCUSSION...
Amplified mid-level flow will persist over the US through the
remainder of the extended forecast period. Continued troughing in
the eastern US will be supported by the arrival of multiple
perturbations from southern Canada over the next week. At the same
time, strong ridging developing over the West will favor
northwesterly flow aloft over the central States. This will allow
for multiple reinforcing surges of cold air to replenish a cold, dry
and stable air mass. Thus, severe thunderstorms are unlikely through
day 8.

..Lyons.. 01/24/2026

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ACUS48 KWNS 250950
SWOD48
SPC AC 250948

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CST Sun Jan 25 2026

Valid 281200Z - 021200Z

...DISCUSSION...
Severe weather concerns are negligible for the extended forecast
period. Continued eastern US troughing, reinforced by northwesterly
flow out of southern Canada will replenish a cold, dry and stable
air mass underneath Arctic high Pressure. While some surface
cyclogenesis appears possible over the eastern Gulf and Atlantic
coast into next weekend, offshore winds should preclude robust
moisture return, negating any thunderstorm or severe risk for the
next several days.

..Lyons.. 01/25/2026

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ACUS48 KWNS 261000
SWOD48
SPC AC 260958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Mon Jan 26 2026

Valid 291200Z - 031200Z

...DISCUSSION...
Severe weather is unlikely through the extended forecast period. A
robust Arctic air mass associated with continued troughing over the
eastern US will be reinforced by several additional perturbations
moving out of Canada and a building western US ridge. As the flow
pattern aloft amplifies, surface cyclogenesis appears possible over
the eastern Gulf and Atlantic seaboard this weekend, further
increasing offshore flow and limiting substantial inland moisture return/destabilization. Thus, thunderstorm potential appears
negligible through the extended forecast period.

..Lyons.. 01/26/2026

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ACUS48 KWNS 270951
SWOD48
SPC AC 270950

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CST Tue Jan 27 2026

Valid 301200Z - 041200Z

...DISCUSSION...
Severe weather potential in the extended forecast period is very
low. Broad-scale eastern US troughing will strengthen this weekend
as a clipper-style trough dives out of Canada an rapidly intensifies
along the Eastern Seaboard. A surface low will develop over the
eastern Gulf and rapidly deepen over the western Atlantic into early
next week. Western US ridging and strong surface high pressure over
the central US will keep substantial inland moisture return unlikely
for the foreseeable future.

..Lyons.. 01/27/2026

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ACUS48 KWNS 280957
SWOD48
SPC AC 280956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Wed Jan 28 2026

Valid 311200Z - 051200Z

...DISCUSSION...
Severe weather is unlikely through the extended forecast period. A
highly amplified mid-level flow pattern over the CONUS will continue
through this weekend and into the first part of next week. A
prominent upper low will amplify over the East Coast as a strong
surface cyclone develops offshore. Ridging over the western US will
support strong high pressure and a cold/dry continental air mass
over much of the US. This will largely suppress inland moisture
transport, outside of far south FL, and subsequent thunderstorm
potential for the next several days.

..Lyons.. 01/28/2026

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ACUS48 KWNS 290943
SWOD48
SPC AC 290942

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CST Thu Jan 29 2026

Valid 011200Z - 061200Z

...DISCUSSION...
Severe weather potential is low through the extended forecast
period. A strong upper low embedded within persistent broad-scale
troughing over the East will move offshore this weekend with several
other perturbations behind it. Continued northwesterly flow aloft
and the passage of several cold fronts early next week will
reinforce a cool air mass over the central US. This will largely
suppress substantial inland moisture return for the foreseeable
future. While some thunderstorm potential may exist along the Gulf
Coast with a more substantial trough passage later next week,
overall thunderstorm/severe potential is very low through the
extended forecast period.

..Lyons.. 01/29/2026

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ACUS48 KWNS 301001
SWOD48
SPC AC 301000

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CST Fri Jan 30 2026

Valid 021200Z - 071200Z

...DISCUSSION...
Northwesterly mid-level flow will continue throughout the Day 4 to 8
period across much of the nation, as a series of shortwave troughs
move southeastward through the flow. Isolated to scattered
thunderstorms will be possible from Tuesday into Wednesday across
parts of the Southeast as a trough moves eastward into the eastern
U.S. Weak moisture return ahead of the trough is expected to keep
the stronger instability over the northern Gulf of America. For this
reason, a severe threat is not forecast with this system. Late in
the week, a cold and dry airmass will likely make thunderstorms
unfavorable across the continental U.S.

..Broyles.. 01/30/2026

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ACUS48 KWNS 310959
SWOD48
SPC AC 310958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Sat Jan 31 2026

Valid 031200Z - 081200Z

...DISCUSSION...
Embedded within broad midlevel troughing over the eastern half of
the CONUS, a shortwave trough will overspread the OH/TN Valleys and
Southeast on Days 4-5/Tuesday-Wednesday. During that time, isolated
to scattered thunderstorms will be possible along an accompanying
cold front as it moves from east TX across the central Gulf Coast.
However, limited moisture/buoyancy ahead of the front should limit
severe potential.

Thereafter, a cold/dry post-frontal air mass will preclude
thunderstorms across the CONUS.

..Weinman.. 01/31/2026

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ACUS48 KWNS 010929
SWOD48
SPC AC 010928

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0328 AM CST Sun Feb 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
A midlevel trough and related cold front will move eastward across
the Southeast and FL Peninsula on Days 4-5/Wednesday-Thursday. While
isolated thunderstorms will be possible along the front as it
overspreads the central/eastern Gulf Coast states, limited
moisture/buoyancy will keep the severe risk low. Thereafter,
strengthening deep-layer northwesterly flow over the MS/OH Valleys
will reinforce large-scale troughing over the eastern U.S. and
western Atlantic. This will favor a prolonged period of dry,
offshore flow -- limiting thunderstorm potential across the CONUS.

..Weinman.. 02/01/2026

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ACUS48 KWNS 020936
SWOD48
SPC AC 020934

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0334 AM CST Mon Feb 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
Broad midlevel troughing will be maintained over the East, while an
upper ridge persists over the Great Plains/Rockies through much of
the extended forecast period. Farther west, medium-range guidance
depicts a midlevel trough/low moving ashore over the West Coast on
Day 5/Friday, before continuing eastward across the Southwest and
eventually toward the southern Plains. Given the cut-off nature of
this disturbance, guidance varies significantly regarding timing,
evolution, and downstream moisture return over the southern Plains
and lower MS Valley late in the period. Nevertheless, current
indications are that the severe risk will remain low though much of
the extended forecast period.

..Weinman.. 02/02/2026

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ACUS48 KWNS 030940
SWOD48
SPC AC 030939

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0339 AM CST Tue Feb 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
On the backside of a broad large-scale trough over the East, dry,
offshore flow will persist across much of the CONUS through at least
Days 5-6/Saturday-Sunday. As a result, thunderstorm potential will
be low during this time frame. Thereafter, medium-range guidance
depicts a low-latitude midlevel trough/low moving eastward across
the Southwest/northern Mexico and eventually into the southern
Plains by Days 7-8/Monday-Tuesday. However, current indications are
that surface high pressure encompassing the eastern half of the
CONUS will limit boundary-layer moisture return and overall severe
potential.

..Weinman.. 02/03/2026

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ACUS48 KWNS 040945
SWOD48
SPC AC 040944

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CST Wed Feb 04 2026

Valid 071200Z - 121200Z

...DISCUSSION...
Medium-range guidance depicts a low-latitude midlevel trough
advancing eastward across parts of Mexico and the Southwest on Days 4-6/Saturday-Monday, before emerging over the southern Plains
vicinity around Day 7/Tuesday. While the timing and overall
evolution of this feature remain uncertain (given substantial model differences), current indications are that the
unconsolidated/split-flow nature of the upper-level pattern and
weakly modified Gulf moisture return will limit severe potential.

..Weinman.. 02/04/2026

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ACUS48 KWNS 050958
SWOD48
SPC AC 050956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Thu Feb 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
A low-latitude midlevel low will advance eastward across northern
Mexico on Days 4-5/Sunday-Monday, before devolving into an open wave
and emerging over the southern Plains on Day 6/Tuesday. While
thunderstorm potential should increase across the region ahead of
this feature, current indications are that weakly modified Gulf
moisture will limit appreciable severe potential -- especially given
modest midlevel lapse rates accompanying the trough.

In the wake of this feature, the upper-level pattern should begin to consolidate and amplify, as a large-scale trough develops over the
West. This should eventually favor higher-quality boundary-layer
moisture return into the southern Plains and lower MS Valley late in
the extended forecast period.

..Weinman.. 02/05/2026

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ACUS48 KWNS 060752
SWOD48
SPC AC 060750

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0150 AM CST Fri Feb 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
An upper low and attendant shortwave trough will be positioned over
northern Mexico and AZ/NM on Day 4/Mon. This system will progress
eastward across TX and the Gulf Coast states/Southeast through Day
6/Wed. As this occurs, a deepening surface low over the Plains will
support southerly returning flow transporting modified Gulf moisture
northward into parts of the south-central and southeast states
through mid-week. Some increase in thunderstorm potential is
possible with this system, though severe potential appears limited
by weak instability and warm midlevel temperatures.

By the end of the period, an upper ridge is forecast over the
south-central and southeast states, maintaining Gulf moisture from
parts of TX into Gulf Coast states on persistent southerly low-level
flow. At the same time, an upper trough is forecast to deepen over
portions of the Plains and Midwest, and a surface cold front will
develop southward toward the Gulf Coast from Thursday night into
Friday (Days 7-8). Some increase in thunderstorm potential will be
possible, though severe potential is uncertain given poor model
run-to-run inconsistency and questions regarding quality of moisture
return.

..Leitman.. 02/06/2026

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ACUS48 KWNS 070853
SWOD48
SPC AC 070851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 AM CST Sat Feb 07 2026

Valid 101200Z - 151200Z

...DISCUSSION...
...Days 4-5/Tue-Wed -- Gulf Coast States...

An upper shortwave trough embedded within broader upper ridging
across the eastern half of the U.S., will move across the Gulf Coast
states Day 4-5/Tue-Wed. Modified Gulf moisture (50s to near 60 F
dewpoints) will overspread portions of the south-central and
southeast CONUS during this time. The upper trough is expected to
weaken as it moves east, and destabilization is expected to remain
meager. While some thunderstorm potential could emerge, severe
thunderstorms are not expected.

...Days 6-8/Thu-Sat - Southern States...

Another upper trough is forecast to move across the Southwest on Day
6/Thu, and continue eastward across the Southeast through Day 8/Sun. Quasi-zonal flow/weak upper riding will persist downstream from this
feature across the southern Plains into the Southeast, allowing for
some degree of modified Gulf moisture to develop near the Gulf Coast
vicinity. However, forecast guidance varies in the strength of the
developing upper trough, and with regards to potential moisture
return across the south-central/southeast states. Some increase in
thunderstorm potential may develop by the end of the period across
the region, but severe potential appears low/uncertain given large
spread among guidance.

..Leitman.. 02/07/2026

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ACUS48 KWNS 080752
SWOD48
SPC AC 080751

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0151 AM CST Sun Feb 08 2026

Valid 111200Z - 161200Z

...DISCUSSION...
Some thunderstorm potential is possible on Day 4/Wed across parts of
the Gulf Coast states as a weakening upper shortwave trough moves
across the Gulf and FL. A cold front will develop southward across
the region, and warm advection atop the front, combined with cooling
aloft may support isolated thunderstorms. However, instability is
expected to remain weak and severe storms are not expected.

Spread among forecast guidance increases heading into the weekend.
However, the general pattern suggests upper ridging will move across
the Plains and Southeast through Day 6/Fri. Meanwhile, another upper
trough will develop over the western U.S., and approach the southern
Plains by late Friday. As surface low pressure develops over the
southern Plains ahead of the upper trough, southerly low-level flow
over the western Gulf will support modest northward transport of at
least shallow Gulf moisture into TX and the Gulf Coast states. As
the upper trough shifts east across the southern Plains and into the
Southeast around Day 7/Sat, some potential for increasing
thunderstorm activity is expected. Given a couple days of increasing
boundary layer moisture, some low severe risk could accompany the
upper trough passage. However, large spread in the timing of this
system, and uncertainty regarding quality of moisture return and
ensuing destabilization preclude a 15 percent severe delineation.

..Leitman.. 02/08/2026

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ACUS48 KWNS 090926
SWOD48
SPC AC 090925

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0325 AM CST Mon Feb 09 2026

Valid 121200Z - 171200Z

...DISCUSSION...
Increasing thunderstorm potential may develop across portions of TX
to the Lower MS Valley and Southeast Days 5-7/Fri-Sun. During this
period, an upper trough will move across the southern Plains and
Southeast U.S. Medium range forecast guidance varies with regard to
timing of eastward progression, and how far north 60s F dewpoints
will develop ahead of the upper trough and attendant surface low.

Notably, the GFS keeps appreciable instability mostly offshore the
Gulf Coast, while ECMWF destabilizes further north into the Gulf
Coast states during the weekend. Meanwhile, SPC GEFS and other ML
guidance depicts only minor severe probability areas. Given the
current forecast strength and track of the associated surface
cyclone across the Lower MS Valley/Southeast, at least some low-end
potential for severe thunderstorms seems possible. Nevertheless, the aforementioned uncertainties, and expected modest thermodynamic
environment even if Gulf moisture spreads further inland, precludes
15 percent severe delineation at this time.

..Leitman.. 02/09/2026

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ACUS48 KWNS 100903
SWOD48
SPC AC 100901

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0301 AM CST Tue Feb 10 2026

Valid 131200Z - 181200Z

...DISCUSSION...
...Days 4-6/Fri-Sun -- TX into the Southeast...

An upper trough is forecast to spread eastward from the Southwest
into the Southeast Days 4-6/Fri-Sun. Beginning on Day 4/Friday,
southwesterly flow will overspread the southern Plains ahead of the
trough and surface low pressure is expected to develop over western
TX. As the system spreads east through the weekend, Gulf moisture
(upper 50s to low 60s F dewpoints) will overspread much of central
to eastern TX toward the Lower MS Valley and Deep South. Some model
spread persists with regards to the timing of eastward progression
of the upper trough, and exact latitude of the surface low (some
guidance clustering further south, other guidance a bit further
north), which will impact quality of moisture return. Regardless, at
least weak destabilization should accompany boundary layer
moistening and cooling aloft amid strengthening deep-layer
southwesterly flow.

Some low-end severe potential is possible from Friday evening
through Saturday across portions of TX, and into the Lower MS
Valley/Deep South Saturday night through Sunday. However, overall
severe potential will likely be limited by weak destabilization, a
somewhat cool boundary layer, and questionable moisture return this
early in the season, precluding 15 percent severe delineation.

..Leitman.. 02/10/2026

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ACUS48 KWNS 110931
SWOD48
SPC AC 110929

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0329 AM CST Wed Feb 11 2026

Valid 141200Z - 191200Z

...DISCUSSION...
...Days 4-5/Sat-Sun -- Texas to the Southeast...

An upper trough will move from the southern High Plains early Day
4/Saturday, eastward across the Deep South/Southeast states through
Day 5/Sunday. An associated belt of enhanced southwesterly flow
ahead of the trough will overspread increasing boundary layer
moisture within a low-level warm advection regime. Meanwhile, a
surface low near the OK/TX Red River Valley early Saturday will
deepen as it shifts east to the TN valley by Sunday morning, before
moving offshore the NC/Mid-Atlantic coast Sunday night. Widespread
showers and scattered thunderstorms are expected to develop within
the warm advection regime ahead of an eastward-advancing cold front,
first across eastern TX to the Lower MS Valley on Saturday/Saturday
night, and continuing across portions of the Deep South and
Southeast on Sunday.

Severe potential remains uncertain, though at least some low-end
severe hazards appear possible given at least some weak
destabilization across the moderate to strongly sheared warm sector.
However, the northern extent of any higher-quality Gulf moisture is
unclear given longitudinal spread among guidance with the placement
of the surface low. Furthermore, given the neutral to positive-tilt
trough and deep-layer flow parallel to the surface boundary,
training precipitation could further limit destabilization. These
uncertainties preclude 15 percent severe delineation at this time.

...Days 6-8/Mon-Wed...

Upper ridging is forecast to move from the Plains to the eastern
U.S. on Day 6/Monday in the wake of the departing upper trough from
the weekend. Model spread increases considerably by the end of the
period, though various guidance hints at a continued progressive
upper pattern, with some potential for another trough developing
over the West early next week. Overall, predictability is low beyond
Monday.

..Leitman.. 02/11/2026

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ACUS48 KWNS 120908
SWOD48
SPC AC 120906

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0306 AM CST Thu Feb 12 2026

Valid 151200Z - 201200Z

...DISCUSSION...
...Day 4/Sun -- Deep South/Southeast...

An upper trough will move across the Deep South and Southeast on Day
4/Sun. Strong deep-layer southwesterly flow atop a modestly moist
boundary layer will support weak destabilization, though how much
remains uncertain as ongoing convection and cloud cover could limit instability. Some risk for strong to isolated severe storms seems
most likely from southern AL/GA into parts of FL as surface low and
trailing cold front move across the region. However, overall risk
appears limited by modest thermodynamics and possible widespread
heavy rain.

...Days 5-8...

On Days 5-6/Mon-Tue, upper level ridging is forecast to spread east
from the Plains to the Midwest and eastern U.S. By Midweek, medium
range guidance generally depicts upper level troughing spreading
across the western U.S. and at least some potential for upper
shortwave trough ejection into parts of the central U.S. However,
forecast spread is large beyond Day 6/Tue. Trends suggest some
increase in thunderstorm potential could develop toward the end of
the forecast period somewhere in the central U.S./Midwest vicinity,
but predictability is low.

..Leitman.. 02/12/2026

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ACUS48 KWNS 131000
SWOD48
SPC AC 130959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Fri Feb 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
It appears that a blocking high/ridge may be maintained across the
southern mid-latitude east central Pacific (roughly near 150W
longitude) through next week. Downstream, the evolution of an
increasingly prominent mid-level high is forecast across the Gulf
Basin through Bahamas/Caribbean vicinity by the end of next week.
However, developments within the branching westerlies across and
inland of the Pacific coast remain more unclear, particularly
subsequent to some initial consolidation of mid-level troughing near
the U.S. Pacific coast by early next week.

Shorter wavelength perturbations emerging from this cyclonic regime
are generally forecast to progress across and east-northeast of the
Rockies, contributing to periodic lee cyclogenesis. The timing of
potentially stronger cyclogenesis has varied within and among the
various model output, including one possible developing cyclone
across the central Great Plains into portions of the Great Lakes and
Ohio Valley during the early into middle portion of next week.
Regardless of the strength, however, guidance has been consistent
indicating that limited warm sector boundary-layer moisture return
will probably tend to inhibit severe thunderstorm development.

Subsequent, renewed (potentially strong) surface cyclogenesis
appears possible to the lee of the Rockies later next week. Model
spread by that time is notable, but an increasing moist southerly
return flow off the Gulf does appear probable, around the western
flank of the subtropical ridge.

..Kerr.. 02/13/2026

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ACUS48 KWNS 140957
SWOD48
SPC AC 140956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Sat Feb 14 2026

Valid 171200Z - 221200Z

...DISCUSSION...
Medium-range model output indicates generally low predictability
concerning the evolution of the blocking pattern over the
mid-latitude central into eastern Pacific, and downstream
developments inland and across North America, through this period.
Most certain, at this time, it appears that a fairly significant
perturbation emerging from Intermountain West on Tuesday will be
accompanied by deep surface troughing overspreading much of the
mid/lower Missouri Valley through the Upper Midwest and Ohio Valley,
before weakening across the Great Lakes on Wednesday. This will be
accompanied by strengthening deep-layer wind fields and shear,
conditionally supportive of organized convective development given
sufficient destabilization. However, there has been little change
from prior model runs, which have indicated that, despite an
initially seasonably warm environment across much of the Great
Plains and Mississippi Valley, the lack of appreciable Gulf moisture
return will inhibit convective potential through at least the middle
of next week.

Thereafter, in the mean, a broadly cyclonic to anticyclonic
southwesterly regime may characterize the flow into next weekend
across the southern Rockies and Great Plains through the Mid
Atlantic, to the west-northwest through north of a fairly prominent
subtropical high shifting from the Gulf Basin into Bahamas/Caribbean
vicinity. It is possible that a short wave embedded within this
regime may support significant lee cyclogenesis, as the Gulf
boundary layer becomes supportive of a more substantive moist return
flow. This, in turn, could become supportive of an increase in
potential for severe thunderstorm development, but a clear and
consistent signal has yet to emerge in the various medium range
guidance.

..Kerr.. 02/14/2026

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ACUS48 KWNS 141001
SWOD48
SPC AC 141000

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0400 AM CST Sat Feb 14 2026

Valid 171200Z - 221200Z

...DISCUSSION...
Medium-range model output indicates generally low predictability
concerning the evolution of the blocking pattern over the
mid-latitude central into eastern Pacific, and downstream
developments inland and across North America, through this period.
Most certain, at this time, it appears that a fairly significant
perturbation emerging from Intermountain West on Tuesday will be
accompanied by deep surface troughing overspreading much of the
mid/lower Missouri Valley through the Upper Midwest and Ohio Valley,
before weakening across the Great Lakes on Wednesday. This will be
accompanied by strengthening deep-layer wind fields and shear,
conditionally supportive of organized convective development given
sufficient destabilization. However, there has been little change
from prior model runs, which have indicated that, despite an
initially seasonably warm environment across much of the Great
Plains and Mississippi Valley, the lack of appreciable Gulf moisture
return will inhibit convective potential through at least the middle
of next week.

Thereafter, in the mean, a broadly cyclonic to anticyclonic
southwesterly regime may characterize the flow into next weekend
across the southern Rockies and Great Plains through the Mid
Atlantic, to the west-northwest through north of a fairly prominent
subtropical high shifting from the Gulf Basin into Bahamas/Caribbean
vicinity. It is possible that a short wave embedded within this
regime may support significant lee cyclogenesis, as the Gulf
boundary layer becomes supportive of a more substantive moist return
flow. This, in turn, could become supportive of an increase in
potential for severe thunderstorm development, but a clear and
consistent signal has yet to emerge in the various medium range
guidance.

..Kerr.. 02/14/2026

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ACUS48 KWNS 151002
SWOD48
SPC AC 151000

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CST Sun Feb 15 2026

Valid 181200Z - 231200Z

...DISCUSSION...
Medium-range model output suggests that amplified large-scale
troughing, initially centered near the Pacific coast at the outset
of the period, will gradually develop eastward, across and east of
the Rockies during the latter half of the week into next weekend.
It appears that this will occur in generally piecemeal fashion, as a
series of smaller-scale/lower amplitude perturbations. However,
given the presence of an initially seasonably warm environment to
the lee of the Rockies, potential exists for periodic lee surface
cyclogenesis, possible strong.

To this point, guidance has exhibited rather poor predictability
with these features, but there does appear at least somewhat greater
certainty in potential for substantive surface cyclogenesis by
Thursday, across the central Great Plains toward the Great Lakes
region. Even so, it still appears that preceding Gulf
boundary-layer moistening and inland return flow will only support
limited moistening within the developing warm sector across the
middle Mississippi Valley through much of the day Thursday. By
Thursday night, there are indications that a modest late moisture
surge into the lower Ohio Valley could contribute to increasing
convective potential, but the extent of the severe threat remains
unclear at this time.

Guidance still indicates that better low-level moisture return may
commence ahead of the cold front trailing the cyclone, across parts
of the Ohio/Tennessee Valleys through Ark-La-Tex and southern Great
Plains Friday into Saturday, as upstream perturbations begin to
emerge from the West. However, current model output suggests that
renewed cyclogenesis may be more subdued, and it is possible that
convection may tend to develop and train along and to the cool side
of the front and/or outflow, with uncertain severe weather
potential.

..Kerr.. 02/15/2026

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ACUS48 KWNS 161002
SWOD48
SPC AC 161000

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CST Mon Feb 16 2026

Valid 191200Z - 241200Z

...DISCUSSION...
Medium-range guidance indicates that a sub-1000 mb surface cyclone,
centered across the central Great Plains at the outset of the
period, may undergo a period of further deepening as it migrates
across and northeast of the lower Missouri Valley, toward the Great
Lakes, late Thursday afternoon or evening. Perhaps most notable,
latest model output appears a bit more aggressive than last night
concerning a corridor of warm sector moisture return into the
vicinity of the confluence of the Mississippi and Ohio Rivers. It
now appears that this may include surface dew points increasing as
high as the upper 50s to lower 60s F by around 20/00Z, which may
advect at least a bit further east-northeastward through the lower
Ohio Valley, before being cut off later Thursday evening. Though
still somewhat modest, and perhaps only supportive of CAPE on the
order of 500 J/kg, this probably will be conducive to severe
thunderstorm development, in the presence of more than sufficient
deep-layer shear and large-scale ascent to support organized
convection. This may include supercells with potential to produce
tornadoes, and perhaps an upscale growing cluster with strong to
severe gusts for a period Thursday evening.

It appears that this cyclone will weaken substantively across the
Great Lakes region on Friday, with renewed cyclogenesis possible to
the east of the Blue Ridge, or perhaps primarily offshore of the Mid
Atlantic coast. So, while increasing low-level moisture return may
continue into the warm sector across parts of the Southeast and Mid
Atlantic, the extent to which mid/upper support remains conducive to
severe weather potential remains unclear.

By late this coming weekend into at least next Monday, convective
potential appears likely to diminish as large-scale mid/upper
ridging expands across and east of the Rockies toward the Atlantic
Seaboard.

..Kerr.. 02/16/2026

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ACUS48 KWNS 170952
SWOD48
SPC AC 170950

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CST Tue Feb 17 2026

Valid 201200Z - 251200Z

...DISCUSSION...
In general, the latest medium-range guidance indicates that an
initially notable surface cyclone over the upper Great Lakes region
at the outset of the period will undergo substantive weakening, as a
supporting short wave impulse becomes sheared and weakens to the
south of a blocking mid-level ridge centered over southern Hudson
Bay. It appears that secondary cyclogenesis across and offshore of
the Mid Atlantic coast Friday through Friday night will be subdued,
with a trailing cold front stalling across the southern Atlantic
through Gulf coast vicinity into Saturday, near the southern
periphery of the seasonably strong westerlies.

Forcing for ascent associated with trailing short wave
perturbations, emerging from larger-scale mid-level troughing
progressing out of the West, may remain largely to the cool side of
the surface frontal zone. However, further moistening along it
could support sufficient destabilization for vigorous, perhaps
upscale growing and training, thunderstorm development, which could
pose at least some risk for producing severe hail and wind. While
severe thunderstorm probabilities are being maintained at less than
15 percent in this outlook, it is still possible that this could
change in later outlook updates for the Friday/Saturday time period.

Thereafter, amplifying mid/upper flow across the eastern
mid-latitude Pacific into North America through early next week
appears likely to include building large-scale ridging inland of the
Pacific coast through the Mississippi Valley. Beneath the confluent
regime in the wake of digging downstream troughing, cold surface
ridging is forecast to build southward to the lee of the Rockies,
through much of the Gulf Basin. Associated low-level drying and
stabilization probably will tend to limit convective potential
through the remainder of the period.

..Kerr.. 02/17/2026

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ACUS48 KWNS 180957
SWOD48
SPC AC 180956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Wed Feb 18 2026

Valid 211200Z - 261200Z

...DISCUSSION...
Latest medium-range guidance indicates little further amplification
of large-scale mid-level troughing across the eastern mid-latitude
Pacific, but a broad embedded cyclonic circulation, with a number of
shorter wavelength perturbations pivoting around its periphery, may
continue to evolve through this coming weekend. These may be
accompanied by multiple areas of surface cyclogenesis, including one
cyclone with an occluding front which may advance into northern
Pacific coastal areas late Saturday night into early Sunday.
However, it appears that the coldest mid-level air, supportive of boundary-layer based destabilization conducive to thunderstorms,
might remain offshore.

At the same time, downstream amplification of mid-level ridging may
continue across the Rockies and Great Plains Saturday into Sunday,
with subsequent amplification of troughing east of the Mississippi
Valley through areas offshore of the southern Atlantic Seaboard
Sunday through Monday. This is likely to be accompanied by cold
surface ridging building south-southeastward to the lee of the
Rockies, through much of the Gulf Basin, which probably will
suppress convective potential through the remainder of the period.

While the environment may be at least conditionally supportive of
strong to severe thunderstorm development along a frontal zone
across parts of the eastern Gulf Coast into southern Atlantic Coast
early this coming weekend, surface frontal wave development across
inland areas on Saturday is forecast to remain weak, tending to
minimize this potential.

..Kerr.. 02/18/2026

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ACUS48 KWNS 190950
SWOD48
SPC AC 190948

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CST Thu Feb 19 2026

Valid 221200Z - 271200Z

...DISCUSSION...
Downstream of initially amplified mid/upper ridging forecast to
expand east of the Rockies through the Mississippi Valley, models
indicate that troughing will amplify further, into and across the
southern Atlantic Seaboard late this coming weekend into early next
week. As it does, much more substantive cyclogenesis appears likely
to ensue offshore of the southern Mid Atlantic coast, toward the
western north Atlantic, while cold surface ridging builds southward
through much of the Gulf Basin before gradually weakening.

Around the same time, and thereafter, guidance indicates that the
blocked regime across the central into eastern mid-latitude Pacific
will become suppressed. It appears that the initially broad
offshore cyclonic mid-level circulation will become more compact,
and remain offshore, while flow inland of the Pacific coast through
the Atlantic Seaboard trends less amplified and generally
west-northwesterly through the middle to latter portion of next
week.

Beneath this regime, surface troughing may initially deepen across
the Great Plains, before a cold front, associated with a short wave perturbation digging from the higher latitudes, advances south of
the Canadian/U.S. border through much of the central and eastern
U.S. by the end of the period. However, even by that time, it
appears that Gulf boundary-layer moistening and inland return flow
will be too limited to support an appreciable risk for severe
storms.

..Kerr.. 02/19/2026

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ACUS48 KWNS 190956
SWOD48
SPC AC 190954

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0354 AM CST Thu Feb 19 2026

Valid 221200Z - 271200Z

...DISCUSSION...
Downstream of initially amplified mid/upper ridging forecast to
expand east of the Rockies through the Mississippi Valley, models
indicate that troughing will amplify further, into and across the
southern Atlantic Seaboard late this coming weekend into early next
week. As it does, much more substantive cyclogenesis appears likely
to ensue offshore of the southern Mid Atlantic coast, toward the
western north Atlantic, while cold surface ridging builds southward
through much of the Gulf Basin before gradually weakening.

Around the same time, and thereafter, guidance indicates that the
blocked regime across the central into eastern mid-latitude Pacific
will become suppressed. It appears that the initially broad
offshore cyclonic mid-level circulation will become more compact,
and remain offshore, while flow inland of the Pacific coast through
the Atlantic Seaboard trends less amplified and generally
west-northwesterly through the middle to latter portion of next
week.

Beneath this regime, surface troughing may initially deepen across
the Great Plains, before a cold front, associated with a short wave perturbation digging from the higher latitudes, advances south of
the Canadian/U.S. border through much of the central and eastern
U.S. by the end of the period. However, even by that time, it
appears that Gulf boundary-layer moistening and inland return flow
will be too limited to support an appreciable risk for severe
storms.

..Kerr.. 02/19/2026

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ACUS48 KWNS 200914
SWOD48
SPC AC 200913

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0313 AM CST Fri Feb 20 2026

Valid 231200Z - 281200Z

...DISCUSSION...
The forecast period will begin with a highly amplified upper-air
pattern with a ridge over the Rockies and a deep trough over the
eastern US. By the middle of the next week, this mid-level flow
regime will transition to one characterized as broadly northwest
flow from the Pacific Northwest toward the Southeast United States.
This flow regime will help drive a mid-level trough/surface cold
front southeast through the Plains toward the end of next week.
However, limited moisture return ahead of this trough/cold front
should temper any severe potential.

The front is expected to push south into at least the northern Gulf.
This resulting cold/dry air intrusion into the northern Gulf will
limit the potential for appreciable moisture return and subsequent thunderstorm/severe thunderstorm potential through the rest of the
forecast period.

..Marsh.. 02/20/2026

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ACUS48 KWNS 210932
SWOD48
SPC AC 210931

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CST Sat Feb 21 2026

Valid 241200Z - 011200Z

...DISCUSSION...
At the start of the forecast period, a dry airmass will remain
across much of the United States. The culprit being a large surface
anticyclone located across the northern Gulf Coast states
suppressing moisture return. By late Tuesday (Day 4), the
anticyclone will have moved into the eastern Gulf, with southerly
winds advecting moisture northward into the Southern Plains.

Thunderstorm chances may return to portions of the Southern Plains
into the Southeast overnight Wednesday into Thursday as a surface
cold front pushes south into the area. At this time, the quality of
the moisture return and poor lapse rates suggests limited, if any,
severe potential as the front moves through.

The aforementioned front will stall/wash out across the northern
Gulf states late on Thursday into Friday (Days 6 and 7) with modest
moisture return developing across the Southern Plains Friday into
Saturday (Days 7 and 8). This will be short lived as ensemble
guidance suggests a seasonably strong cold front moving into/through
the Southern Plains next weekend or early the following week. Once
again, current guidance indicates the quality of moisture return and
poor lapse rates should limit any severe potential.

..Marsh.. 02/21/2026

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ACUS48 KWNS 221000
SWOD48
SPC AC 220958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Sun Feb 22 2026

Valid 251200Z - 021200Z

...DISCUSSION...
A sharp mid-level trough will move across the US early in the
forecast period (Wednesday and Thursday -- Days 4 and 5). This wave
will induce surface cyclogenesis across the Central Plains on
Wednesday, and this low will quickly move east across the Ohio
Valley on Thursday. Southerly winds ahead of the low will draw Gulf
moisture northward across much of the Southeast.

Showers and perhaps a few thunderstorms will develop on Thursday
along and head of an eastward advancing cold front to the south of
the aforementioned surface low. Forecast soundings and low-level
wind fields show strong low-level wind fields atop a cool, moist
boundary layer. Despite little to any instability, strong
convergence along the cold front may support a narrow band of forced
ascent. Given the strength of the low-level wind fields, a few
strong wind gusts may reach the surface across portions of the
Tennessee Valley on Thursday afternoon/evening, even absent
lightning. Confidence in the specifics of this evolution are too low
to warrant severe probabilities, but will be monitored in subsequent
forecasts.

This cyclone will push a front south toward the northern Gulf coast
by Friday, where southward advancement will stall. This front should
wash out/redevelop northward next weekend as southerly flow takes
hold and begins to advect moisture northward.

..Marsh.. 02/22/2026

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ACUS48 KWNS 230838
SWOD48
SPC AC 230837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0237 AM CST Mon Feb 23 2026

Valid 261200Z - 031200Z

...DISCUSSION...
The upper-air pattern across the US will remain characterized as
broad, fast, northwest flow for most of the forecast period.
Embedded within this flow, a series of shortwave troughs will move
across the US. The first, and potentially most impactful of these
troughs will move across the eastern US on Thursday and Friday (Days
4 and 5).

A surface low will develop across portions of the Tennessee Valley
early in the day Thursday in response to increasing large-scale
ascent associated with the aforementioned shortwave trough. This low
will quickly move east then northeast, pushing a cold front through
much of the Southeast US. A couple days of moisture return will
result in surface dewpoints in the 50Fs to perhaps low 60Fs ahead of
this cold front. Despite poor lapse rates and meager buoyancy
profiles, strong convergence along the front should yield a narrow
band of forced ascent/convection. A strong low-level jet and curved
low-level hodographs indicated in forecast soundings may support a
few isolated damaging wind gusts or perhaps a brief tornado or two
with this convection, even absent widespread lightning. Although
confidence is increasing that a band of strongly forced convection
will occur along the cold front, confidence remains too low in where
damaging wind gusts/brief tornado may occur to introduce
unconditional 15% severe probabilities.

In the wake of this cold front, the severe potential looks to be
rather limited as surface moisture is suppressed south into the
northern Gulf until next weekend at the earliest, when southerly
return flow should develop across Texas and Oklahoma.

..Marsh.. 02/23/2026

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ACUS48 KWNS 240947
SWOD48
SPC AC 240946

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0346 AM CST Tue Feb 24 2026

Valid 271200Z - 041200Z

...DISCUSSION...
The severe potential will remain low through this forecast period as
the atmosphere undergoes a pattern change.

Ensemble guidance is in good agreement that in the wake of a
departing trough, a frontal boundary will stall across the northern
Gulf Coast on Friday (Day 4), largely confining appreciable
low-level moisture to the Gulf. The front remains loosely in place
until late this weekend (Sunday -- Day 6) when it washes out and
redevelops farther north. This occurs coincident with a transition
of the upper-air pattern from a single belt of broadly northwest
flow to a split flow regime (ridge over trough).

By early next week (Days 7 and 8) an expansive upper-level ridge
will take shape across much of the US while a closed low develops
and then opens up beneath this ridge across the Southwest. The
position and evolution of the closed low should place modest
southwest flow across much of the Plains by the end of the forecast
period. Southerly winds to the east of the resulting High Plains lee
trough should support a gradual moistening of the Plains' low-level environment.

Although ensemble guidance is in relatively good agreement about the large-scale pattern evolution, considerable differences exist with
the finer details, such as quality and northward extent of the
moisture return, timing of specific feature evolution, and resulting
placement of any precipitation potential -- including thunderstorms.
In any event, the overall resulting pattern and pattern recognition
favors an increase in thunderstorm and perhaps severe potential
across the central US just beyond this forecast period.

..Marsh.. 02/24/2026

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ACUS48 KWNS 250954
SWOD48
SPC AC 250953

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CST Wed Feb 25 2026

Valid 281200Z - 051200Z

...DISCUSSION...
Ensemble guidance continues to support a large-scale change to the
overall upper-air pattern during this forecast period. The western ridge/eastern trough should flip, evolving toward a western trough
and eastern ridge. As this happens, southwest mid-level flow into
the central US will support a gradual warming/moistening of the
Plains' low-level environment. Details of how far north and the
overall quality of the moisture return remain to be seen.

This moisture return will begin in earnest on Saturday (Day 4) as
southerly winds take hold across the central US. However, a cold
front will suppress this low-level moisture south into central Texas
on Sunday and Monday (Days 5 and 6), with some guidance members
suggesting a reinforcing frontal push on Tuesday.

By the middle of next week (Days 7 and 8), the frontal boundary
should weaken across Texas and redevelop northward. This will allow
low-level moisture to begin advancing northward into the Central
Plains. However the speed and strength of this low-level moisture
advection varies greatly between different ensembles and even within
the membership of specific ensembles. As such, the overall potential
for organized severe weather on any day looks to be too low for
unconditional probabilities. However, pattern recognition suggests
thunderstorm (and severe) potential should increase across portions
of the central US just beyond this forecast period.

..Marsh.. 02/25/2026

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ACUS48 KWNS 251040
SWOD48
SPC AC 251039

Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0439 AM CST Wed Feb 25 2026

Valid 281200Z - 051200Z

...DISCUSSION...
Ensemble guidance continues to support a large-scale change to the
overall upper-air pattern during this forecast period. The western ridge/eastern trough should flip, evolving toward a western trough
and eastern ridge. As this happens, southwest mid-level flow into
the central US will support a gradual warming/moistening of the
Plains' low-level environment. Details of how far north and the
overall quality of the moisture return remain to be seen.

This moisture return will begin in earnest on Saturday (Day 4) as
southerly winds take hold across the central US. However, a cold
front will suppress this low-level moisture south into central Texas
on Sunday and Monday (Days 5 and 6), with some guidance members
suggesting a reinforcing frontal push on Tuesday.

By the middle of next week (Days 7 and 8), the frontal boundary
should weaken across Texas and redevelop northward. This will allow
low-level moisture to begin advancing northward into the Central
Plains. However the speed and strength of this low-level moisture
advection varies greatly between different ensembles and even within
the membership of specific ensembles. As such, the overall potential
for organized severe weather on any day looks to be too low for
unconditional probabilities. However, pattern recognition suggests
thunderstorm (and severe) potential should increase across portions
of the central US just beyond this forecast period.

..Marsh.. 02/25/2026

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ACUS48 KWNS 260958
SWOD48
SPC AC 260956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Thu Feb 26 2026

Valid 011200Z - 061200Z

...DISCUSSION...
Early in the forecast period a transition across the western US will
take place as the low-amplitude ridge over the Great Basin/Southwest
shifts eastward, giving way to an amplifying trough over the West.
Several speed maxima are forecast to traverse the flow while it
remains primarily northwesterly over the central US early in the
period. At the surface, uncertainty remains regarding the southern
extent of the arctic front pushing into the Plains on Day 3.
Uncertainties in the position of this front will cause low
confidence in the projected quality of the low-level moisture
recovery across the southern Plains through Tuesday. As the
upper-air pattern across the central US transitions from
northwesterly to southwesterly, and return flow commenses, the
shallow nature of the modified arctic airmass may initially limit
the northward penetration of the richest theta-e air.

As the period progresses into Wednesday and Thursday, ensemble
guidance remains in general agreement regarding the transition to an
amplified western trough and central-to-eastern ridge. However, the
timing and phasing of individual shortwaves moving into the Plains
remains a source of forecast uncertainty.

The first meaningful shortwave is forecast to eject into the Plains
early Wednesday, inducing surface cyclogenesis that should support a
northward advancement of the warm sector. Any severe risk with this
trough on Wednesday (Day 7) will be predicated on the evolution of
the moisture return on prior days.

On Thursday, a second, more potent trough is forecast to approach
the Plains. Current ensemble guidance shows quite a bit more
variance with the timing, amplitude, and evolution of this second
trough. Some guidance brings this wave out as single, potent trough,
with other guidance suggesting a series of more subtle shortwave
troughs ejecting into the Plains from Thursday into Saturday. These discrepancies will have an impact on the location, timing, and
magnitude of any potential severe weather threat.

Despite these timing differences, the synoptic setup (increasing
low-level moisture, strengthening southwest flow aloft, repeated
cyclogenesis) is favorable for organized severe weather over the
Plains and lower Mississippi Valley. While the severe weather threat
should increase by Wednesday and Thursday (Days 7 and 8), the
specific orientation of frontal boundaries and the northward extent
of the moisture return will be highly dependent on the evolution of
the upper-lows. Given that models tend to struggle with handling the
details of pattern changes, will hold off on trying to highlight any
specific corridor for severe probabilities for Wednesday and
Thursday at this time.

..Marsh.. 02/26/2026

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ACUS48 KWNS 271001
SWOD48
SPC AC 270959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Fri Feb 27 2026

Valid 021200Z - 071200Z

...DISCUSSION...
...Monday/Day 4 to Tuesday/Day 5...
At mid-levels, a trough is forecast to move across California on
Monday as zonal flow remains in place over the central and eastern
U.S. On Tuesday, the trough is forecast to move eastward across the
Desert Southwest, as flow becomes southwesterly in the south-central
states. A moist airmass will likely be in place on Monday and
Tuesday from eastern parts of the southern Plains into the lower to
mid Mississippi Valley. Thunderstorm development will be possible
each afternoon and evening across parts of the moist airmass. In
areas that destabilize the most, a marginal severe threat may
develop.

...Wednesday/Day 6 to Friday/Day 8...
On Wednesday, the trough is forecast to move into the southern and
central High Plains, as an associated mid-level jet ejects
northeastward across the southern High Plains. At the surface, a
cold front is forecast to move into the southern Plains, as a moist
airmass spreads northward from north Texas into southern and eastern
Oklahoma. As surface temperatures warm during the day, thunderstorms
appear most likely to form along the cold front, and further south
across parts of the warm sector. Moderate deep-layer shear is
evident on model forecasts which should support a severe threat
during the afternoon and evening, with a potential for large hail
and severe wind gusts. While confidence is high enough to add a
severe threat area across the southern Plains, variance does exist
concerning the timing of the shortwave trough. If the trough moves
across the southern Plains faster, then the area could need to be
adjusted.

On Thursday, the mid-level trough is forecast to eject northeastward
into the Great Lakes region, as a large upper-level trough digs into
the Desert Southwest. Southwesterly mid-level flow will likely be in
place over parts of the Great Plains, with a moist and unstable
airmass remaining over much of Texas and Oklahoma. As surface
temperatures warm, isolated strong to severe storms will be possible
in areas that destabilize the most. At this time, there is
uncertainty regarding the magnitude of the threat because some
solutions move a shortwave ridge northeastward across the
south-central U.S.

On Friday, model forecasts suggest that a large-scale upper-level
trough will move through the western U.S. Ahead of this feature,
thunderstorms will continue to be possible over parts of the
southern and central Plains, where a moist and unstable airmass is
forecast to be in place. However, a significant amount of variance
exists among the model solutions, suggesting that uncertainty is
substantial concerning the magnitude and spacing of any severe
threat.

..Broyles.. 02/27/2026

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ACUS48 KWNS 280954
SWOD48
SPC AC 280952

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CST Sat Feb 28 2026

Valid 031200Z - 081200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
On Tuesday, a mid-level trough will move eastward across the Desert
Southwest, as southwesterly flow remains in place over the southern
Plains. As the trough approaches Tuesday night, scattered elevated thunderstorms will be possible from the Red River northeastward into
the mid Mississippi Valley. From Tuesday night into Wednesday, a
moist airmass will spread northward from east-central Texas into the
Arklatex and Ozarks. Thunderstorm development will be possible near
the boundary from central Oklahoma into southern Missouri during the
day on Wednesday, and further southeast across the warm sector in
the afternoon and evening. Model forecasts continue to show moderate instability ahead of the front. In addition, a mid-level jet streak
is forecast to pass through the southern Plains during the
afternoon, creating deep-layer shear sufficient for severe storms.
Supercells with wind damage and isolated large hail will be
possible. Model solutions are in better agreement this run,
suggesting the severe threat will be a bit further east than was
previously forecast. For this reason, the severe threat area has
been adjusted eastward towards the Ark-La-Tex.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, the shortwave trough is forecast to move through the
mid Mississippi Valley, as the cold front advances southeastward
into the Ark-La-Tex and mid Mississippi Valley. Thunderstorms will
be possible near the front during the day into the evening.
Deep-layer shear and instability are forecast to be somewhat
limited, which should keep any severe threat marginal.

From Thursday night into Friday, southwesterly mid-level flow is
forecast to strengthen over the south-central states. In response,
moisture advection will likely continue over the southern Plains as
moderate instability re-develops across much of the southern Plains.
Scattered thunderstorms should form over parts of this airmass
Thursday night from west-central Texas north-northeastward into
parts of the central Plains. The potential for storm development
should continue into Friday along the northern edge of the moist
airmass from north-central Texas northeastward into the Ozarks.
Although a severe threat could develop over parts of the southern
Plains and Ozarks Friday afternoon and evening, there is
considerable uncertainty, mainly due to variance among model
solutions.

On Saturday, am amplified upper-level trough is forecast to develop
over the western U.S., as mid-level flow becomes south-southwesterly
from the Gulf Coast States into the mid Mississippi Valley. A moist
airmass is forecast over much of the Gulf Coast states, where
scattered thunderstorms will be possible during the day. Although a
severe threat could develop during the day, uncertainty is high
concerning the placement of a more concentrated severe threat area.

..Broyles.. 02/28/2026

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ACUS48 KWNS 011001
SWOD48
SPC AC 010959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Sun Mar 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
...Wednesday/Day 4 to Thursday/Day 5...
On Wednesday, model forecasts continue to move a mid-level shortwave
trough across the southern Plains. A cold front is forecast to
advance southeastward into Oklahoma as a moist and unstable airmass
resides southward from the front over much of the southern Plains.
Surface dewpoints across southeast Oklahoma and north-central to
northeast Texas should be in the lower to mid 60s F, and moderate
instability will be possible by afternoon. Thunderstorm development
appears likely across parts of this unstable airmass from the mid
afternoon into the evening. Moderate deep-layer shear should support
a severe threat, with a potential for large hail and damaging wind
gusts associated with supercells.

On Thursday, the shortwave trough is forecast to move into the mid
Mississippi Valley, as a much larger upper-level trough moves
through the Desert Southwest. A moist and unstable airmass should
remain in place over the southern Plains. However, large-scale
ascent should be weak between these two systems, which should dampen
the severe potential across most of the south-central U.S. The most
likely location for an isolated to marginal severe threat would be
in the Ark-La-Tex Thursday afternoon.

...Friday/Day 6 to Sunday/Day 8...
At mid-levels, southwest flow is forecast across much of the central
U.S. on Friday, as a large trough remains over the southwestern
states. Moisture advection is expected to continue over the Great
Plains and Upper Midwest along a corridor of strong low-level flow.
Model forecasts are in general agreement that moderate instability
will develop over much of this airmass by Friday afternoon, and that
scattered thunderstorms will form. Convective development will be
supported by the right entrance region of a mid-level jet ejecting northeastward through the central Plains. This mid-level jet will be
associated with moderate to strong deep-layer shear, supporting
scattered severe storms potentially across a large part of the moist
sector. The current thinking is that the severe threat will be
maximized during the late afternoon and evening from central Texas northeastward into the lower Missouri Valley. Large hail and
damaging wind gusts are expected to the primary threats, but a few
tornadoes remain possible.

On Saturday, the upper-level system in the central U.S. is forecast
to move into the Great Lakes region, as a cold front advances
quickly southeastward into the western Gulf Coast states, and lower
Mississippi Valley. An isolated severe threat could develop ahead of
the front Saturday afternoon, but confidence is low concerning the
spatial distribution of any threat. On Sunday, isolated to scattered thunderstorms will again be possible in the Gulf Coast region.
However, deep-layer shear is forecast to be weak over much of this
area, suggesting any severe potential should remain marginal.

..Broyles.. 03/01/2026

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ACUS48 KWNS 020959
SWOD48
SPC AC 020958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Mon Mar 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
...Thursday/Day 4 and Friday/Day 5...
At mid-levels, a shortwave trough is forecast to move through the
mid Mississippi Valley on Thursday as flow remains southwesterly
across the south-central U.S. An upper-level system will be located
in the Desert Southwest. At the surface, moisture advection is
forecast across the southern Plains, where surface dewpoints will be
mostly in the 50s and 60s F by afternoon. As surface temperatures
warm during the day, an axis of moderate instability is forecast to
develop to the east of a dryline from west-central Texas
north-northeastward into the eastern Texas Panhandle and western
Oklahoma. Along this axis of instability, moderate deep-layer is
forecast, along with steep mid-level lapse rates. This will likely
support a severe threat during the afternoon and evening. Supercells
with large hail, damaging wind gusts and a tornado threat will be
possible.

On Friday, mid-level southwesterly flow will strengthen across parts
of the southern and central Plains, as a mid-level jet ejects
northeastward into the central U.S. At the surface, a moist airmass
with moderate instability is forecast to be in place by afternoon
from north-central Texas north-northeastward into the lower Missouri
Valley. Model forecasts are in agreement that scattered
thunderstorms will develop across this unstable airmass during the
afternoon and evening. Moderate deep-layer shear and steep mid-level
lapse rates should be favorable for supercells with large hail. Wind
damage and tornadoes will also be possible with supercells and
bowing line segments. Some solutions suggest that the threat will
persist into the overnight period as a low-level jet ramps up across
the region.

...Saturday/Day 6 to Monday/Day 8...
Mid-level southwesterly flow is expected to continue over the
south-central U.S. on Saturday, as a cold front moves southward
across the southern Plains and Ozarks. To the south of the front,
the models forecast pockets of moderate instability, and suggest
that scattered to numerous thunderstorms will develop. In addition,
moderate to strong deep-layer shear is forecast across the northern
edge of the moist sector. Model consensus suggests that a severe
threat will develop Saturday afternoon and evening, mainly from
west-central Texas northeastward into the western Ozarks.

The cold front is forecast to continue moving southward into the
western Gulf Coast states on Sunday. Scattered thunderstorms are
forecast to develop near and to the south of the front Sunday
afternoon, where an isolated severe threat will be possible.
Confidence is low concerning the spatial distribution of any
potential threat. On Monday, a shortwave ridge is forecast to move
over the top of a moist airmass in the southern Plains. This
scenario could support an isolated severe threat in the afternoon.
However, uncertainty is high at this range in the forecast period.

..Broyles.. 03/02/2026

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ACUS48 KWNS 030954
SWOD48
SPC AC 030952

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CST Tue Mar 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
...Friday/Day 4 and Saturday/Day 5...
A strong upper-level system is forecast to eject northeastward into
the central High Plains on Friday, as an associated 60 to 80 knot
mid-level jet translates northeastward ahead of the trough. At the
surface, a moist and unstable airmass will likely be in place from
central and east Texas northward into the lower Missouri Valley.
Warming surface temperatures and increasing low-level convergence
will support scattered convective initiation to the west of the
moist axis. Storms are expected to grow upscale in the mid to late
afternoon, moving eastward toward an axis of strong low-level flow.
Moderate instability, strong deep-layer shear and steep lapse rates
will be favorable for supercells. Supercells should be capable of
producing tornadoes, large hail and severe wind gusts. The greatest
potential is forecast from near the Red River in north Texas north-northeastward across eastern Oklahoma into eastern Kansas and northwestern Missouri, where a 30 percent contour has been added. A
severe threat is also forecast northeastward into parts of the mid
to upper Mississippi Valley, where strong deep-layer shear and
sufficient low-level moisture will be in place for a severe threat.

On Saturday, the upper-level system is forecast to move through the north-central U.S., as a cold front advances southeastward into the
Ark-La-Tex, mid Mississippi Valley, and lower Great Lakes. Scattered
to numerous thunderstorms are expected to develop ahead of the front
during the day as surface temperatures warm. It appears that a
marginal severe threat will develop during the mid to late afternoon
over much of the northwestern edge of the moist sector from the
Ark-La-Tex northeastward into the Ohio Valley.

...Sunday/Day 6 to Tuesday/Day 8...
On Sunday in the mid-levels, a 90 to 110 knot jet is forecast to
move into the northern U.S., as westerly flow remains over much of
the east-central U.S. A front is forecast to become quasi-stationary
from the Ozarks eastward into the southern Appalachians. Isolated to
scattered thunderstorms with a marginal severe threat may develop to
the south of the front during the afternoon.

On Monday and Tuesday, moisture advection is forecast to take place
from the central Plains into the Great Lakes, as mid-level flow
again becomes southwesterly. Moisture and instability should be
favorable for isolated severe storms Monday afternoon in areas that
heat up sufficiently. On Tuesday, models forecast a strong
upper-level system to eject northeastward into the south-central
U.S. If this scenario works out, a greater severe threat appears
possible Tuesday afternoon and evening over the southern and central
Plains. However, uncertainty is considerable at this range in the
forecast period due to a relatively wide spread in the model
guidance.

..Broyles.. 03/03/2026

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ACUS48 KWNS 040958
SWOD48
SPC AC 040956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Wed Mar 04 2026

Valid 071200Z - 121200Z

...DISCUSSION...
...Saturday/Day 4 and Sunday/Day 5...
On Saturday at mid-levels, a shortwave trough is forecast to move
eastward across the north-central U.S., as flow remains
southwesterly from the southern Plains to the Eastern Seaboard. A
cold front is forecast to move southeastward across the southern
Plains, Ozarks, mid Mississippi Valley and Ohio Valley. Surface
dewpoints ahead of the front are forecast to be mostly in the 60s F
with pockets of moderate instability developing in the afternoon.
Scattered to numerous thunderstorms are expected to develop and move southeastward into the moist airmass. Although an isolated severe
threat will be likely in some areas, uncertainty is considerable
concerning the area with the greatest severe threat. The current
thinking is that the severe threat will be concentrated in two
areas, with one being from south-central Texas northeastward into
northern Louisiana, and a second being located in the Ohio Valley. A
15 percent area may need to be added in either of these two areas in
later outlooks.

On Sunday, a moist and unstable airmass is forecast along the
western Gulf Coast. Isolated storms associated with a marginal
severe threat could develop in the afternoon. Large-scale ascent
will be limited which should keep any severe potential localized.

...Monday/Day 6 to Wednesday/Day 8...
West-southwesterly mid-level flow is forecast to continue on Monday
across much of the central and eastern U.S. Low-level moisture
return is forecast to take place over the southern and central
Plains, where the models suggest moderate instability will be
possible by afternoon. As a low-level jet strengthens during the
afternoon and evening, isolated to scattered thunderstorms should
develop in areas that heat up sufficiently. A severe threat would be
possible. However, spatial uncertainty exists concerning where any
severe threat will be the greatest.

On Tuesday, model forecasts are in general agreement, moving an
upper-level trough northeastward into the southern High Plains. An
associated mid-level jet is forecast to eject northeastward ahead of
the system. Model forecasts suggest that the airmass ahead of the
trough will become moderately unstable by Tuesday afternoon. This
combined with strong large-scale ascent should support scattered
severe storms in the afternoon and evening. The favored severe
threat area is expected from parts of the southern and central
Plains eastward into the Ozarks.

On Wednesday, the upper-level trough is forecast to move across the south-central U.S., as a cold front advances eastward into the
Southeast. A severe threat may again develop Wednesday afternoon as
the airmass ahead of the front becomes unstable. However, there is
considerable model spread concerning the timing of features at this
extended range.

..Broyles.. 03/04/2026

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ACUS48 KWNS 050938
SWOD48
SPC AC 050936

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0336 AM CST Thu Mar 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
...Sunday/Day 4 and Monday/Day 5...
A moist airmass in the Gulf Coast region on Sunday will advect
northward into the east-central U.S. on Monday. Over the top of this
airmass, west-southwesterly mid-level flow will be in place.
Although large-scale ascent is forecast to be limited on both days,
isolated strong to marginally severe thunderstorms will be possible
in the afternoon in areas that heat up sufficiently. The greatest
potential for severe storms appears to be on Monday afternoon in the Ark-La-Tex, where moisture and low-level flow are currently forecast
to be maximized.

...Tuesday/Day 6 to Thursday/Day 8...
On Tuesday, model forecasts move an upper-level system across
northern Mexico, and retain southwesterly mid-level flow over much
of the south-central U.S. A moist and unstable airmass is forecast
over much of the southern and central Plains eastward into the lower
to mid Mississippi Valley. It appears that large-scale ascent
associated with the upper-level trough will gradually increase over
the southern and central Plains on Tuesday. In response, scattered thunderstorms should develop over parts of the moist sector Tuesday
afternoon and evening. Although model forecasts have slowed the
progression of the upper-level low, a belt of strong mid-level flow
is still forecast over the south-central U.S. on Tuesday. This
suggests that deep-layer shear will support severe thunderstorm
development, potentially across a broad area. The severe threat is
expected to continue from evening into the overnight period as the
upper-level trough approaches.

On Wednesday, the upper-level trough and an associated cold front is
forecast to move into the western Gulf Coast states. Ahead of the
system, a moist and unstable airmass appears likely by afternoon.
Thunderstorms that develop near and ahead of the front could have a
severe threat. However, there are still questions about the timing
of the trough and front. If model runs continue to suggest that the
system will move into the western Gulf Coast states on Wednesday,
then a risk area may need to be added. An isolated risk may also
develop on Wednesday northeastward ahead of the front in parts of
the Tennessee and Ohio Valleys.

On Thursday, the upper-level trough is forecast to move into the
eastern U.S., as the cold front moves offshore into the western
Atlantic. Thunderstorms with an isolated severe threat would be
possible along parts of the Eastern Seaboard before the front
passes. However, uncertainty at this extended range is considerable.

..Broyles.. 03/05/2026

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ACUS48 KWNS 060940
SWOD48
SPC AC 060938

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CST Fri Mar 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
...Day 4/Monday...

A weak upper shortwave impulse is expected to migrate across the
Ozarks/Lower MS Valley on Monday. This will support a narrow
corridor of enhanced westerly flow aloft atop a moistening boundary
layer. Isolated thunderstorms may develop across the ArkLaTex to
Lower MS Valley vicinity within the warm advection regime, and few
storms could become strong to locally severe. However, modest
forcing and otherwise lack of low-level focus precludes a 15 percent delineation.

...Day 5/Tuesday into Day 6/Wednesday...

An upper low and attendant shortwave trough over northwest Mexico is
forecast to eject eastward toward the southern High Plains on
Tuesday. At the same time, a broad upper trough within northern
stream flow will develop east from the northern Plains to the Upper
Midwest. As this occurs, a belt of enhanced southwesterly flow aloft
will overspread a large warm/moist sector from the southern Plains
to the Mid/Lower MS and Ohio Valleys. A complex surface pattern is
expected to emerge, influenced by the split-flow upper troughing
pattern. A baroclinic zone extending from OK the Mid-MS Valley area
will be one focus for severe thunderstorm potential. Meanwhile, lee
surface troughing across west TX and a developing dryline will be
another focus for severe storm development. While details remain
uncertain, these surface features, combined with strengthening
southwesterly flow overspreading a warm and unstable airmass, will
likely foster a broad area of severe thunderstorm potential from the
southern Plains into the Midwest.

As the upper troughs from Day 5/Tuesday continue east across the
southern Plains and Great Lakes on Day 6/Wednesday, a cold front is
expected to develop southeast across the Ohio Valley into east
Texas. Spread among forecast guidance increases during this time,
leading to more uncertainty. However, most guidance has some overlap
of favorable low-level moisture and instability with stronger
mid/upper level flow across portions of east TX into the Lower MS
valley. As a result, a 15 percent area has been delineated. This
area my need to shift/expand northeast with time depending on trends
in model guidance, but currently, it is uncertain if sufficient
destabilization will occur further northeast, precluding severe
probabilities into the TN/OH Valleys vicinity.

...Days 7-8/Thursday-Friday...

Predictability is low toward the end of the forecast period as
forecast model spread continues to increase. While it is plausible
some severe risk could persist into the Southeast on Day 7/Thursday
as the upper trough over the Lower MS Valley continues to migrate
east, uncertainty is too high to include probabilities at this time.

..Leitman.. 03/06/2026

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ACUS48 KWNS 061047
SWOD48
SPC AC 061046

Day 4-8 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0446 AM CST Fri Mar 06 2026

Valid 091200Z - 141200Z

CORRECTED FOR TEXT

...DISCUSSION...
...Day 4/Monday...

A weak upper shortwave impulse is expected to migrate across the
Ozarks/Lower MS Valley on Monday. This will support a narrow
corridor of enhanced westerly flow aloft atop a moistening boundary
layer. Isolated thunderstorms may develop across the ArkLaTex to
Lower MS Valley vicinity within the warm advection regime, and a few
storms could become strong to locally severe. However, modest
forcing and otherwise lack of low-level focus precludes a 15 percent delineation.

...Day 5/Tuesday into Day 6/Wednesday...

An upper low and attendant shortwave trough over northwest Mexico is
forecast to eject eastward toward the southern High Plains on
Tuesday. At the same time, a broad upper trough within northern
stream flow will develop east from the northern Plains to the Upper
Midwest. As this occurs, a belt of enhanced southwesterly flow aloft
will overspread a large warm/moist sector from the southern Plains
to the Mid/Lower MS and Ohio Valleys. A complex surface pattern is
expected to emerge, influenced by the split-flow upper troughing
pattern. A baroclinic zone extending from OK to the Mid-MS Valley
area will be one focus for severe thunderstorm potential. Meanwhile,
lee surface troughing across west TX and a developing dryline will
be another focus for severe storm development. While details remain
uncertain, these surface features, combined with strengthening
southwesterly flow overspreading a warm and unstable airmass, will
likely foster a broad area of severe thunderstorm potential from the
southern Plains into the Midwest.

As the upper troughs from Day 5/Tuesday continue east across the
southern Plains and Great Lakes on Day 6/Wednesday, a cold front is
expected to develop southeast across the Ohio Valley into east
Texas. Spread among forecast guidance increases during this time,
leading to more uncertainty. However, most guidance has some overlap
of favorable low-level moisture and instability with stronger
mid/upper level flow across portions of east TX into the Lower MS
Valley. As a result, a 15 percent area has been delineated. This
area may need to shift/expand northeast with time depending on
trends in model guidance, but currently, it is uncertain if
sufficient destabilization will occur further northeast, precluding
severe probabilities into the TN/OH Valleys vicinity.

...Days 7-8/Thursday-Friday...

Predictability is low toward the end of the forecast period as
forecast model spread continues to increase. While it is plausible
some severe risk could persist into the Southeast on Day 7/Thursday
as the upper trough over the Lower MS Valley continues to migrate
east, uncertainty is too high to include probabilities at this time.

..Leitman.. 03/06/2026

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ACUS48 KWNS 070836
SWOD48
SPC AC 070834

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 AM CST Sat Mar 07 2026

Valid 101200Z - 151200Z

...DISCUSSION...
...Days 4-5/Tue-Wed...

An active pattern with severe thunderstorm potential is expected
Tuesday and Wednesday from the southern Plains to the Mid/Lower MS
and OH Valleys. Medium range guidance is in fairly good agreement
during this time. Starting on Tuesday, an upper low over northern
Mexico will shift east/northeast, becoming an open wave as it begins
to merge with a northern stream upper trough developing southeast
across the northern/central Plains through early Wednesday. A belt
of strong southwesterly deep-layer flow will overspread a large warm
sector on Tuesday. Lee cyclogenesis is forecast across the
central/southern High Plains, along with a second surface low
developing over IA as the northern stream upper trough approaches.
This setup will allow for a sharpening dryline/Pacific front across
the southern Plains, while a cold front develops southeast into the
MO/Mid-MS Valley overnight. Strong ascent should focus thunderstorm
development across the warm sector ahead of these surface boundaries
within a strongly sheared environment, and potentially widespread
severe thunderstorm activity is possible.

The large-scale upper trough and attendant surface cold front will
continue to progress eastward on Wednesday. Uncertainty does
increase, especially with north and east extent of severe potential.
How far east convection develops on Tuesday and how much downstream destabilization occurs is somewhat unclear. Nevertheless, a
deepening surface cyclone is forecast to develop northeast from the
Great Lakes into Ontario and Quebec, while strong deep layer
southwesterly flow overspreads a moist warm sector ahead of the
surface front. This should set the stage for at least isolated to
scattered severe thunderstorm potential along the length of the cold
front through Wednesday evening.

Given uncertainties mentioned above, these areas are likely to be
adjusted in coming days as details become better resolved, but the
overall pattern should support a couple of active severe weather
days over a broad area.

...Day 6/Thu...

Uncertainty increases by Thursday as spread among medium range
guidance increases quite a bit with respect to the evolution/timing
of the upper trough. Some severe potential could persist/develop
across the Mid-Atlantic region, but predictability is too low to
include a 15 percent delineation at this time.

Beyond Thursday, severe thunderstorm potential will likely be low as
the upper pattern become lower amplitude and stronger westerly flow
remains confined to the northern tier of the U.S., along with Gulf
moisture largely remaining offshore behind the cold frontal passage.

..Leitman.. 03/07/2026

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ACUS48 KWNS 080916
SWOD48
SPC AC 080914

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0414 AM CDT Sun Mar 08 2026

Valid 111200Z - 161200Z

...DISCUSSION...
...Day 4/Wed...

A large-scale upper trough will continue to shift east across the
central U.S. on Wednesday, becoming oriented from the Upper Great
Lakes to the central Gulf coast vicinity by Thursday morning. An
embedded shortwave within the base of this trough will move from the
southern Plains to the Deep South, while the northern branch of the
trough moves across the Midwest. Strong deep-layer southwesterly
flow will overspread a broad warm sector across much of the Midwest
and southern U.S. Meanwhile, a cold front will develop southeast
through the period, tracking across much of the Mid/Lower MS, OH and
TN Valleys.

Uncertainty exists regarding where convection may be ongoing
Wednesday morning, and some potential exists for widespread
thunderstorm activity across parts of the Midwest. As a result, it
is uncertain how far north quality thermodynamics will exist.
Nevertheless, it appears likely at least some severe risk will exist
across the Ohio Valley given favorable boundary-layer moisture and
impressive vertical shear profiles. Further southwest toward the
Lower MS Valley into the Deep South vicinity, morning convection may
be more limited compared to further north, allowing for more
extensive destabilization ahead of the surging cold front. A
mixed-mode of supercells ahead of the cold front, and an organized
line of storms along the cold front will be possible across this
area.

As mesoscale details become better resolved in the coming days, the
severe area for Wednesday is likely to shift some. However, the
overall pattern suggests a broad area of severe thunderstorm
potential is probable on Wednesday.

...Day 5/Thu...

Some severe thunderstorm potential could persist into portions of
the Mid-Atlantic and Southeast. However, uncertainty is fairly high
given this potential will depend on evolution of convection on Day
4/Wed, which could be quite extensive and outpace the surface front
Wednesday night into early Day 5/Thu. As such, predictability is
low.

...Days 6-8/Fri-Sun...

Severe thunderstorm potential appears low during the weekend as
broad upper troughing persists across the central/eastern U.S.

..Leitman.. 03/08/2026

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ACUS48 KWNS 090833
SWOD48
SPC AC 090831

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CDT Mon Mar 09 2026

Valid 121200Z - 171200Z

...DISCUSSION...
...Day 4/Thu...

Some low-end severe thunderstorm risk could persist into Day 4/Thu
across portions of the Southeast as an upper trough pivots toward
the Atlantic coast in tandem with an eastward-advancing surface cold
front. Ahead of the front, a moist airmass will be in place from
GA/FL northeast toward southeast VA. Convection will likely be
ongoing Thursday morning, and persistent warm advection will result
in widespread cloudiness. This will limit destabilization and lapse
rates are expected to remain modest. Overall, severe potential
appears less than 15 percent.

...Days 5-8/Fri-Mon...

Severe thunderstorm potential appears low Friday and Saturday as a
prior cold frontal passage into the Gulf leaves a dearth of boundary
layer moisture in its wake. Another upper trough is expected to
deepen over the Plains and the eastern U.S. late in the period. Some
moisture return may occur ahead of this feature before another cold
front develops southeast across the eastern half of the CONUS. This
could bring some increasing thunderstorm potential to parts of the south-central or southeast U.S., however, at this time any better
moisture return looks displaced to the south of stronger flow aloft.

..Leitman.. 03/09/2026

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ACUS48 KWNS 100748
SWOD48
SPC AC 100747

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0247 AM CDT Tue Mar 10 2026

Valid 131200Z - 181200Z

...DISCUSSION...
Severe thunderstorm potential will remain low on Days 4-5/Fri-Sat as
a cold frontal passage and surface high pressure over the central
U.S. leave a dry/stable airmass across much of the CONUS east of the
Rockies.

On Saturday, lower-amplitude, quasi-zonal flow over much of the U.S.
will amplify as a shortwave upper trough deepens over the Rockies
and emerges over the High Plains by Day 6/Sunday morning. As this
occurs, modest Gulf moisture will return northward across east TX
into the Mid-South. A strong surface low is forecast to move across
the Upper Midwest on Sunday as the upper trough continues to dig and
shift east into the Midwest. This will bring a cold front southeast
across portions of the Plains and Midwest. Some severe potential
could develop across central portions of the U.S. on Day 6/Sunday as
the cold front sweeps eastward, but confidence is low given a lack
of deeper moisture return overlapping with stronger shear across the
Midwest.

As the upper trough and surface cold front continue east on Day
7/Monday, some low-end severe potential could possibly develop
across the Mid-Atlantic to the Southeast, but confidence is low
given similar concerns to those on Day 6/Sunday. With this system
moving offshore by the end of the period, severe potential appears
low on Day 8/Tuesday.

..Leitman.. 03/10/2026

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ACUS48 KWNS 110754
SWOD48
SPC AC 110752

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0252 AM CDT Wed Mar 11 2026

Valid 141200Z - 191200Z

...DISCUSSION...
...Days 4-6/Sat-Mon...

An upper trough will begin to deepen as it moves over the northern
Rockies and into the northern/central High Plains on
Saturday/Saturday night. As this occurs, a lee cyclone will deepen
as it shifts east across the central Plains toward the MO Valley by
early Sunday. Modified Gulf moisture will return northward in
response to increasing southerly low-level flow ahead of the surface
cyclone and attendant cold front. Medium range guidance is in fairly
good agreement that any deeper/higher quality moisture will remain
confined to east TX and the immediate Gulf coast on Sunday. With
northward extent into the Mid-South, Mid-MS and Lower OH, and TN
Valleys, 50s F dewpoints appear more likely. The upper trough will
intensify and shift east across the Midwest and south-central U.S.
on Sunday, but stronger flow aloft will remain displaced from better
quality moisture return. While some severe potential could develop
from east TX into the Lower OH/TN Valleys as a strong cold front
tracks east across the central U.S. on Sunday, probabilities appear
less than 15 percent at this time.

This system will shift east across the eastern U.S. on Monday,
though any severe potential along the East Coast appears low at this
time as the primary forcing for ascent lags behind the surface
front.

...Days 7-8/Tue-Wed...

An amplified upper ridge will build across the western U.S. during
the end of Tuesday and Wednesday while upper troughing persists
across the East. Surface high pressure and the prior cold frontal
passage into the Gulf will leave a stable and dry airmass in place,
precluding severe potential.

..Leitman.. 03/11/2026

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ACUS48 KWNS 120817
SWOD48
SPC AC 120815

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0315 AM CDT Thu Mar 12 2026

Valid 151200Z - 201200Z

...DISCUSSION...
...Day 4/Sunday - ArkLaTex/Lower MS Valley into the Middle MS/Lower
OH Valleys...

An intense upper trough will deepen over the Plains and shift east
to the MS Valley on Sunday. From late afternoon into the nighttime
hours, an 80-100 kt jet streak will develop within the base of the
trough and overspread portions of the region. At the surface, an
already strong cyclone will deepen further as it moves from the
Lower MO Valley to the Lower Great Lakes vicinity. As this occurs, a
strong cold front will sweep eastward across the southern Plains and
much of the Midwest and Southern U.S., becoming oriented from Ohio
to the FL Panhandle by Monday morning.

While strengthening southerly low-level flow will develop ahead of
the front, stronger Gulf moisture return will be confined to TX and
the Lower MS Valley vicinity, with mainly 50s dewpoints expected
with northward extent across the Middle MS and OH Valley regions.
Furthermore, capping is expected ahead of the cold front,
potentially limiting warm sector convection. Nevertheless, modest
moisture and steepening midlevel lapse rates will support at least
weak destabilization very near the cold front. A narrow line of
strongly-forced convection is expected to develop along the cold
front and move across portions of OK/TX into the Middle/Lower MS and
Lower OH/TN Valley regions. Given intense deep-layer flow near and
just behind the cold front, strong/damaging wind potential will
exist within a modest instability/high shear environment. A 15
percent severe delineation has been included from the ArkLaTex into
the Mid-South/Lower MS Valley vicinity. Depending on low-level moisture/instability trends, this area may need to be expanded north
and east into a larger portion of the Middle MS/Lower OH/TN Valley
vicinity in subsequent outlooks.

...Day 5/Monday - Southeast to Mid-Atlantic...

Severe thunderstorm potential will likely continue into Monday as
the intense upper trough continues to migrate east from the MS
Valley toward the Eastern Seaboard. Intense deep-layer southwesterly
flow will overspread portions of the Southeast to the Mid-Atlantic.
Meanwhile, 60s F dewpoints will extend from southeast GA northward
through the Mid-Atlantic ahead of a sharp cold front. Pre-frontal
surface troughing across the VA/NC Piedmont also will support
backing low-level winds, leading to enhanced low-level shear.
Depending on how much cloud cover and warm advection precipitation
occurs ahead of the cold front, stronger destabilization may be
inhibited. Nevertheless, at least weak instability is forecast ahead
of a strongly forced line of convection along the eastward-advancing
cold front. This activity alone could produce a swath of strong to
severe wind gusts. A more conditional risk of supercells across the
warm sector exists across eastern VA/NC, but this is more uncertain.
Given damaging wind potential with the strongly forced linear
convection, a 15 percent severe delineation has been added for
portions of the region.

...Days 6-8/Tuesday-Thursday...

Severe thunderstorm potential will be low Tuesday through Thursday
as strong surface high pressure builds in the wake of the earlier
cold frontal passage. A dry/stable airmass will prevail as Gulf
moisture remains well offshore.

..Leitman.. 03/12/2026

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ACUS48 KWNS 130900
SWOD48
SPC AC 130858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Fri Mar 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
Significant severe winds and the potential for a few tornadoes will
develop on Monday over parts of the Carolinas and Mid Atlantic.

Models are in good agreement with the large scale pattern on
Monday/D4, depicting a deep upper trough moving out of the
Mississippi Valley and ejecting in negative-tilt fashion across the
Mid Atlantic and into to the Northeast.

Given the antecedent upper ridging on the previous day, low-level
southerly winds will help to moisten the air mass well ahead of an
approaching cold front. By 12Z Monday, 60s F dewpoints will already
extend from northern GA across the Piedmont and into southeast VA,
and this plume of moisture will rapidly spread north with near 60 F
dewpoints into southeast PA by 00Z.

There appears to be two regimes for severe potential on Monday.
First, up to 1000 J/kg MUCAPE may develop well ahead of the
approaching cold front, and there is some indication that scattered
convection may occur across the warm sector from mid to late
afternoon. If this occurs, supercells would be most likely, with
potential for a few tornadoes from the Carolinas into eastern VA.

Models also indicate an elongated pressure fall/rise couplet, which
when combined with 50-70 kt 850 mb winds and extreme low-level
shear, could easily result in a QLCS along the cold front with
corridors of significant damaging winds and embedded tornado risk.

Beyond Monday/D4, stable air behind this system will likely preclude
any severe threat through Friday/D8.

..Jewell.. 03/13/2026

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ACUS48 KWNS 131953
SWOD48
SPC AC 131951

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Fri Mar 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
Significant severe winds and the potential for a few tornadoes will
develop on Monday over parts of the Carolinas and Mid Atlantic.

Models are in good agreement with the large scale pattern on
Monday/D4, depicting a deep upper trough moving out of the
Mississippi Valley and ejecting in negative-tilt fashion across the
Mid Atlantic and into to the Northeast.

Given the antecedent upper ridging on the previous day, low-level
southerly winds will help to moisten the air mass well ahead of an
approaching cold front. By 12Z Monday, 60s F dewpoints will already
extend from northern GA across the Piedmont and into southeast VA,
and this plume of moisture will rapidly spread north with near 60 F
dewpoints into southeast PA by 00Z.

There appears to be two regimes for severe potential on Monday.
First, up to 1000 J/kg MUCAPE may develop well ahead of the
approaching cold front, and there is some indication that scattered
convection may occur across the warm sector from mid to late
afternoon. If this occurs, supercells would be most likely, with
potential for a few tornadoes from the Carolinas into eastern VA.

Models also indicate an elongated pressure fall/rise couplet, which
when combined with 50-70 kt 850 mb winds and extreme low-level
shear, could easily result in a QLCS along the cold front with
corridors of significant damaging winds and embedded tornado risk.

Beyond Monday/D4, stable air behind this system will likely preclude
any severe threat through Friday/D8.

..Jewell.. 03/13/2026

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ACUS48 KWNS 132006
SWOD48
SPC AC 132004

Day 4-8 Convective Outlook AMEND 1
NWS Storm Prediction Center Norman OK
0304 PM CDT Fri Mar 13 2026

Valid 161200Z - 211200Z

AMENDED TO EXPAND D4/MONDAY THREAT AREAS

...DISCUSSION...
...Updated discussion for D4...
The majority of deterministic and ensemble model guidance agree on a
deep midlevel trough and associated cold front that will move
eastward across the Appalachians and to the Atlantic coast by
Tuesday morning. Severe storms could be ongoing at the beginning of
the period along the northeast Gulf coast into GA. The warm sector, characterized by boundary-layer dewpoints in the 60s, will expand
northward (generally east of the Appalachians) through the day as
far north as PA. Though clouds could limit downstream surface
heating somewhat, very strong wind profiles and focused forcing for
ascent will favor a continuation of convection along the front, as
well as pre-frontal convection, with the potential to produce
relatively widespread damaging winds and several tornadoes.

...Previous discussion below...
Significant severe winds and the potential for a few tornadoes will
develop on Monday over parts of the Carolinas and Mid Atlantic.

Models are in good agreement with the large scale pattern on
Monday/D4, depicting a deep upper trough moving out of the
Mississippi Valley and ejecting in negative-tilt fashion across the
Mid Atlantic and into to the Northeast.

Given the antecedent upper ridging on the previous day, low-level
southerly winds will help to moisten the air mass well ahead of an
approaching cold front. By 12Z Monday, 60s F dewpoints will already
extend from northern GA across the Piedmont and into southeast VA,
and this plume of moisture will rapidly spread north with near 60 F
dewpoints into southeast PA by 00Z.

There appears to be two regimes for severe potential on Monday.
First, up to 1000 J/kg MUCAPE may develop well ahead of the
approaching cold front, and there is some indication that scattered
convection may occur across the warm sector from mid to late
afternoon. If this occurs, supercells would be most likely, with
potential for a few tornadoes from the Carolinas into eastern VA.

Models also indicate an elongated pressure fall/rise couplet, which
when combined with 50-70 kt 850 mb winds and extreme low-level
shear, could easily result in a QLCS along the cold front with
corridors of significant damaging winds and embedded tornado risk.

Beyond Monday/D4, stable air behind this system will likely preclude
any severe threat through Friday/D8.

..Thompson.. 03/13/2026

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ACUS48 KWNS 140851
SWOD48
SPC AC 140850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Sat Mar 14 2026

Valid 171200Z - 221200Z

...DISCUSSION...
On Tuesday/D4, a large upper trough will move across the Northeast,
though the associated surface cold front will already be well
offshore the East Coast with high pressure over land. Behind this
upper trough, models indicate a large upper ridge will be situated
over the Southwest for several days, with a northwest flow pattern
across the Plains. Given this pattern, minimal appreciable moisture
return is expected over the CONUS, and severe storms appear unlikely
through Saturday/D8.

..Jewell.. 03/14/2026

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ACUS48 KWNS 150852
SWOD48
SPC AC 150850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Sun Mar 15 2026

Valid 181200Z - 231200Z

...DISCUSSION...
Severe storms appear unlikely across the CONUS for the D4-8 period,
as an upper ridge holds over the Southwest with a mean upper trough
over the East. This pattern will keep a surface high over much of
the east/southeast CONUS, with northerly winds over the Gulf Of
America for much of the period.

Models do indicate the upper ridge over the Southwest may weaken
into the Sat/D7 and Sun/D8 time frame, with perhaps the pattern
trending toward zonal. Even so, potential for any significant
instability to develop over land remains minimal.

..Jewell.. 03/15/2026

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ACUS48 KWNS 160648
SWOD48
SPC AC 160646

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0146 AM CDT Mon Mar 16 2026

Valid 191200Z - 241200Z

...DISCUSSION...
A northwest flow regime will persist across the Plains through
Saturday/D6 as an upper high holds over the southwestern states. The
ridge is expected to break down late D6 through the remainder of the
period into Monday/D8, as a strong wave moves southeastward into the
Great Lakes, and a weaker wave potentially moves into the Great
Basin/Four Corners states on Sunday/D7. This overall pattern will
maintain relatively stable conditions over most of the CONUS, with
high pressure over the southeastern states including the Gulf of
America. Further, as the stronger wave potentially moves across the
Great Lakes and into the Northeast, a reinforcing cold front is
likely to plunge south over much of the central and eastern states
into the D7/D8 time frame. While limited moisture may precede this
cold front, overall potential for destabilization appears to be
minimal.

..Jewell.. 03/16/2026

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ACUS48 KWNS 170614
SWOD48
SPC AC 170612

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0112 AM CDT Tue Mar 17 2026

Valid 201200Z - 251200Z

...DISCUSSION...
An upper ridge will hold over the Southwest from Fri/D4 into Sat/D5,
but will begin to flatten as a progressive, low-amplitude wave moves
into the far northern Rockies and Plains. This feature is then
forecast to amplify across the Great Lakes and Northeast during the
Sun/D6 to Tue/D8 period, while an upper ridge possibly re-builds
over the Southwest. However, predictability becomes low for that
pattern change.

In association with the northern wave, low pressure with a trailing
cold front may develop from the Plains to the Mid Atlantic from
Sun/D6 into Mon/D7. Given the antecedent dry conditions, only
marginal moisture return and destabilization are expected. While
this may support scattered thunderstorms across the Ohio Valley
region on Sunday/D6, substantial severe weather is not anticipated.

Behind that system, a reinforcing high will likely spread south
across the Plains and much of the East, resulting in stable
conditions.

..Jewell.. 03/17/2026

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ACUS48 KWNS 180719
SWOD48
SPC AC 180717

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0217 AM CDT Wed Mar 18 2026

Valid 211200Z - 261200Z

...DISCUSSION...
An upper ridge is forecast to break down across the Southwest late
Saturday/D4 into Sunday/D5, with a weak wave embedded in the
northwesterly flow regime aloft. During the same time, a stronger
but low-amplitude feature will move rapidly east/southeast along the
Canadian border, across the Great Lakes and into the Northeast.

In association with the northern/Great Lakes disturbance, a cold
front is forecast to push south into the Plains on Sunday/D5,
extending into the OH Valley by late in the day. This front will
interact with marginal moisture return across the Mid MS/OH Valleys,
and continue into the Southeast on Monday/D6. This front is forecast
to be roughly parallel to the upper flow, and would likely undercut thunderstorms that develop along it. MUCAPE on the order of 500-1000
J/kg seems reasonable, which will support marginal severe at best.

For the latter days of the period, the forecast becomes less
predictable, however, models on a run to run basis appear to be
trending toward higher heights/possible ridging over the Southwest,
with little to no threat of severe storms.

..Jewell.. 03/18/2026

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ACUS48 KWNS 190901
SWOD48
SPC AC 190859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Thu Mar 19 2026

Valid 221200Z - 271200Z

...DISCUSSION...
On Sunday/D4, thunderstorms will be possible over parts of the OH
Valley into the Appalachians, and perhaps as far south as the TN
Valley, as an upper trough amplifies across the upper MS Valley and
into the Great Lakes. A cold front is forecast to extend
southwestward from a low over NY/PA, with perhaps lower 60s F
dewpoints and MUCAPE on the order of 500-1500 J/kg possible. Models
appear to have a wide range of instability values for Sunday, and as
such predictability is low. However, there is at least some
potential for strong to perhaps a few severe storms over the mid to
upper OH Valley. The most likely scenario is for a marginal setup
given the northwest flow pattern and modest-moisture-content warm
sector.

This front will push south toward the Gulf Coast on Monday/D5, with
high pressure building in to the north. The upper trough will move
across the Northeast on Monday, with another possibly amplifying
across the Great Lakes/Northeast Tuesday/D6 into Wednesday/D7. As
this occurs, an upper ridge is likely to exist across the Southwest,
with little overall severe potential for those days.

..Jewell.. 03/19/2026

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ACUS48 KWNS 200844
SWOD48
SPC AC 200842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Fri Mar 20 2026

Valid 231200Z - 281200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
An upper-level trough is forecast to move across the eastern U.S. on
Monday, as a cold front advances southward into the Carolinas.
Thunderstorm development will be possible in parts of the Carolinas
Monday afternoon. Instability is forecast to be weak, but a marginal
severe threat could develop in areas that heat up the most.

On Tuesday and Wednesday, northwest mid-level flow is forecast over
much of the eastern two-thirds of nation. This pattern will keep a
warm and dry airmass in place over the continental U.S., making
thunderstorms unlikely in most areas.

...Thursday/Day 7 and Friday/Day 8...
Mid-level flow is forecast to become more westerly across the
central and eastern U.S. on Thursday. In response, low-level
moisture return is forecast from the Ark-La-Tex into the mid
Mississippi Valley. Thunderstorm development will be possible from
Thursday afternoon into the overnight period across the lower to mid
Missouri Valley into the Ohio Valley, as a mid-level jet streak
passes through the north-central U.S. On Friday, a continued chance
for thunderstorm development will be possible from the mid
Mississippi Valley into the southern Appalachians. Although a severe
threat may develop on either Thursday or Friday, low predictability
exists concerning any specific scenario.

..Broyles.. 03/20/2026

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ACUS48 KWNS 210831
SWOD48
SPC AC 210829

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0329 AM CDT Sat Mar 21 2026

Valid 241200Z - 291200Z

...DISCUSSION...
...Tuesday/Day 4 to Thursday/Day 6...
An upper-level trough is forecast to move eastward into the western
Atlantic from Tuesday into Wednesday, as a surface high moves
eastward across the eastern U.S. A dry airmass is forecast across
most of the U.S., which should be unfavorable for thunderstorms in
most areas.

On Thursday, a low is forecast to develop in the northern U.S., as
low-level moisture returns quickly northward into the parts of the
Great Plains and Mississippi Valley. Thunderstorms will be possible
across this unstable airmass, mainly Thursday night, along the
southern edge of a passing mid-level jet streak. The greatest
potential for severe thunderstorms is expected from the mid
Mississippi Valley into the Ohio Valley along and near a cold front.
At this time, the amount of spread concerning potential outcomes is substantial. An area may need to be added once model solutions begin
to agree more, and confidence increases concerning where the
greatest severe threat will be.

...Friday/Day 7 and Saturday/Day 8...
On Friday, the front is forecast to move southward across the
Tennessee Valley, where isolated to scattered strong thunderstorms
will be possible during the day. The front is forecast to move
southward to near the Gulf Coast by Saturday. Isolated storms would
again be possible near the front. Although the current thinking is
that any severe threat will be marginal on Friday and Saturday,
uncertainty is substantial due to the extended range in the forecast
period.

..Broyles.. 03/21/2026

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ACUS48 KWNS 220842
SWOD48
SPC AC 220840

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0340 AM CDT Sun Mar 22 2026

Valid 251200Z - 301200Z

...DISCUSSION...
...Wednesday/Day 4 to Thursday/Day 5...
An upper-level ridge will move into the Rockies on Wednesday, as
northwesterly mid-level flow remains from the Great Plains to the
eastern U.S. On Thursday, the ridge will become less amplified as it
moves into the Great Plains. At the surface, low-level moisture is
forecast to return northward into the lower to mid Mississippi
Valley. Within this moist airmass, a pocket of moderate instability
is expected by late Thursday afternoon. Thunderstorm development
will be possible near a front along the northern edge of the
stronger instability from northeast Missouri east-northeastward into north-central Ohio. Storms are expected to move east-southeastward
across the Ohio Valley on Thursday afternoon and evening. A severe
threat will be possible, but the magnitude of any potential threat
is still uncertain.

...Friday/Day 6 and Sunday/Day 8...
From Friday into Saturday, a cold front is forecast to move
southward from the mid Mississippi Valley to the central Gulf Coast.
Isolated thunderstorms will be possible along parts of the front
both Friday and Saturday afternoon. Weak instability should keep any
severe threat marginal.

On Sunday, the models are forecasting a dry airmass over most of the continental U.S., suggesting the potential for storms is low.

..Broyles.. 03/22/2026

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ACUS48 KWNS 230900
SWOD48
SPC AC 230859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Mon Mar 23 2026

Valid 261200Z - 311200Z

...DISCUSSION...
...Thursday/Day 4 and Friday/Day 5...
Strong westerly mid-level flow will be in place across much of the
central and eastern U.S. on Thursday. At low-levels, moisture
advection is forecast to strengthen during the day from the mid
Mississippi Valley into the lower Ohio Valley as surface dewpoints
gradually increase into the lower to mid 60s F. A cold front is
forecast to advance southeastward into the southern Great Lakes by
Thursday afternoon, with scattered to numerous thunderstorms
developing along and near the front. Moderate instability should
develop to the south of the front, which combined with strong
deep-layer shear will likely support a severe threat during the
afternoon and evening. The greatest threat is expected to be from
northeast Missouri east-northeastward into western and northern
Ohio, where a threat area has been added for Thursday.

On Friday, a mid-level trough is forecast to dig southeastward into
the mid Mississippi Valley, as a front moves southeastward into the
Tennessee Valley and southern Appalachians. Although isolated to
scattered thunderstorms will be possible near the front during the
afternoon and evening, model forecasts suggest that instability will
remain relatively weak. This should keep any severe threat minimal.

...Saturday/Day 6 to Monday/Day 8...
The cold front is forecast to move southward through the Southeast
on Saturday and should remain near the Gulf Coast on Sunday. In its
wake, a relatively dry airmass is forecast to be in place over much
of the nation, making thunderstorm development unlikely in most
areas. On Monday, some model forecasts suggest that a mid-level
shortwave trough will move into the southern Plains. Low-level
moisture could return northward into the southern Plains Monday into
Monday night. If this where to occur, then thunderstorm activity
would be mostly likely Monday night as a low-level jet develops.
However, this scenario is highly uncertain due to the extended range
in the forecast period.

..Broyles.. 03/23/2026

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ACUS48 KWNS 240844
SWOD48
SPC AC 240842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Tue Mar 24 2026

Valid 271200Z - 011200Z

...DISCUSSION...
Widespread severe thunderstorm potential appears limited through the
remainder of March amid persistent upper-level ridging across the
central and western CONUS. Isolated to scattered thunderstorms may
materialize across portions of the TN Valley and Mid-Atlantic on
D4/Friday as a strong cold front pushes east/southeast towards the
East Coast and northern Gulf. However, limited mid-level lapse rates
across the southeastern U.S. will likely modulate the potential for
severe thunderstorms. Surface high pressure building across the
eastern Plains and OH Valley in the wake of the cold front -
combined with the re-amplification of the upper ridge over the
western U.S. - will further limit severe thunderstorm potential for
much of the weekend and very early next week.

A gradual eastward translation of the surface high will likely
promote the initial stages of moisture into the central U.S. around
the D7/Mon or D8/Tues time frame. Most deterministic solutions and
ensemble systems hint at an upper-level regime shift as the upper
ridge shifts east and southwesterly flow becomes more prominent over
the Southwest. This may support some increase in severe weather
potential by the middle of next week, and possibly as early
D8/Tuesday, but predictability at this range appears very limited.

..Moore.. 03/24/2026

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ACUS48 KWNS 250846
SWOD48
SPC AC 250844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Wed Mar 25 2026

Valid 281200Z - 021200Z

...DISCUSSION...
Severe thunderstorm potential remains limited for this weekend,
though a gradual increase in some severe threat is anticipated by
the middle of next week. In the wake of a cold frontal passage on
D3/Friday into D4/Saturday, surface high pressure building over the
eastern Plains and OH Valley will maintain dry and stable conditions
for most regions east of the Rockies. Concurrently, a slight
re-amplification of an upper-level ridge this weekend over the
Southwest/West Coast will maintain warm and dry conditions for the
southwestern CONUS. Long-range ensemble guidance continues to show a
reasonably consistent signal in the slow eastward migration of the
upper ridge through early next week. As this occurs, surface high
pressure will gradually shift off the East Coast and promote
moisture return into the Plains and MS Valley. Tight clustering of
GEFS members lends high confidence in the potential for a return of
slightly above seasonal moisture by the D6/Monday to D7/Tuesday time
frame. Thunderstorm chances should steadily increase through
mid-week as southwesterly flow aloft becomes increasingly
predominant and promotes ascent/lapse-rate advection over the
northwestern fringe of the returning moisture. Extended-range
guidance hints at severe thunderstorm potential through the
D6/Monday to D8/Wednesday time frame - mainly across the upper MS Valley/Midwest within the warm conveyor region of an organizing
cyclone. While confidence in the overall synoptic evolution through
next week is high, notable run-to-run variability in the convective
environment forecast beyond D6 suggests predictability remains too
limited to warrant highlights at this time.

..Moore.. 03/25/2026

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ACUS48 KWNS 260850
SWOD48
SPC AC 260848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Thu Mar 26 2026

Valid 291200Z - 031200Z

...DISCUSSION...
Severe weather potential will remain low through the end of the
upcoming weekend, and while a gradual increase in severe weather
potential is anticipated through next week, predictability remains
limited. Extended-range deterministic and ensemble solutions
continue to generally show good agreement in the eastward
translation of the upper ridge currently over the Southwest towards
the East Coast through the middle of next week. This will not only
result in increasing southwesterly flow over the central CONUS, but
will also promote lee troughing/cyclogenesis with an attendant
uptick in moisture return into the Plains/MS Valley.

Recent GEFS forecasts show high confidence in a return of slightly
above seasonal moisture into the eastern Plains and Midwest by the
D5/Monday to D6/Tuesday time frame. Severe thunderstorm potential is
expected to generally increase during this period as weak impulses
embedded within the broader southwest flow regime overspread the
returning moisture. Based on more bullish deterministic solutions,
some severe risk may materialize across the Midwest late D5/Monday
into D6/Tuesday within a warm frontal zone, and potentially across
the central Plains on D7/Wednesday or D8/Thursday as a cold front
pushes southeast in tandem with the intensification of a surface
low.

While these signals are noted, run-to-run variability among
deterministic guidance remains fairly high regarding the
evolution/placement of surface features and convective environments
beyond D6/Tuesday. Latest GEFS and ECENS guidance, as well as
long-range ensemble clustering and extended calibrated guidance,
show a substantial increase in variance by mid-week, which implies
limited confidence in any particular solution. While not surprising
at this range and with an upper-level regime shift yet to occur, it
remains unclear when predictability of any mid-week severe threat
will substantially improve.

..Moore.. 03/26/2026

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ACUS48 KWNS 270855
SWOD48
SPC AC 270853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Fri Mar 27 2026

Valid 301200Z - 041200Z

...DISCUSSION...
An uptick in severe thunderstorm potential is expected through the
upcoming work week and heading into next weekend. Long-range
ensemble guidance continues to show a strong signal for a return to
mean troughing across the western to central CONUS as a long-wave
ridge gradually de-amplifies and shifts east. This upper-level flow
regime will promote steady lee troughing/cyclogenesis along the High
Plains, which in conjunction with the placement of a surface high
off the East Coast, will promote moisture return northward into the
Plains and MS Valley. Strong to severe thunderstorms appear possible
multiple days next week as ascent associated with upper disturbances
embedded within the mean flow regime overspread the moisture plume.

...D4/Monday - Upper Mississippi Valley...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border during the D4/Monday to D5/Tuesday time frame. As this
occurs, surface cyclogenesis is expected across the northern Plains.
A broad swath of isentropic ascent with in the warm conveyor of the
developing cyclone will likely support showers and isolated to
scattered thunderstorms across portions of the upper MS Valley late
Monday. A few deterministic solutions, notably the recent 00z ECMWF,
hint that the convective environment will be conducive for organized convection, including the potential for elevated supercells.
However, ensemble agreement regarding this potential is limited.

...D5/Tuesday - Lake Michigan Vicinity...
Confidence is gradually increasing in a regional severe weather
threat across parts of the upper Great Lakes for D5/Tuesday. Over
the past 24 hours, model guidance has come into somewhat better
agreement regarding the timing and evolution of the northern Plains
surface low through as it translates east and intensifies across the
Great Lakes region Tuesday into early Wednesday. Above-seasonal
moisture return northward into the Great Lakes region is anticipated
by late Tuesday, which should support adequate buoyancy for deep
convection. Thunderstorm development appears likely along a trailing
cold front as it pushes southeast into the Midwest and MS Valley.
Based on ensemble guidance, the best convective environment may
reside across the Lake Michigan vicinity where mid/upper-level flow
should be stronger in vicinity to the upper jet and may be more
orthogonal to the front and supportive of more robust convection
compared to locations further south.

Despite the trend towards a more consolidated solution, notable
discrepancies remain pertaining to the propagation speed of the
upper wave and surface low, which introduces uncertainty in how
favorably timed the strongest ascent will be with peak
heating/destabilization and potential storm modes. These
uncertainties preclude probabilities at this time, but highlights
will likely be introduced as model consensus improves.

..Moore.. 03/27/2026

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ACUS48 KWNS 280858
SWOD48
SPC AC 280856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Sat Mar 28 2026

Valid 311200Z - 051200Z

...DISCUSSION...
A return to a more seasonal upper-level regime will promote
strong/severe thunderstorm chances beginning D4/Tuesday and
potentially persisting into the upcoming weekend. A well-anticipated upper-level regime shift remains likely late this weekend and into
early next week as an upper ridge over the south-central CONUS
de-amplifies and shifts east. The return to mean troughing over the
West will promote persistent lee troughing and southerly return flow
into the Plains and lower MS Valley. Long-range guidance depicts
several upper disturbances propagating across the northern and
central U.S. through late week, which may each support some risk of strong/severe thunderstorms.

...D4/Tuesday...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border and into the Great Lakes region Monday into Tuesday.
Northeastward moisture return ahead of an intensifying surface
cyclone and trailing cold front will likely establish a fairly broad
warm sector from the Ozarks into the Midwest/Great Lakes region.
Thunderstorm development along the cold front is expected by late
afternoon with most deterministic and ensemble guidance showing
strong QPF signals. Any severe weather threat will likely be focused
from central IL northeastward into northern IN/southern MI where
deep-layer wind shear will be stronger in proximity to the upper jet
and shear vectors should be more orthogonal to the front. While some
solutions depict favorable MLCAPE and shear for organized convection
(e.g. the 00z GFS), ensemble consensus shows muted probabilities for
a highly favorable convective environment (e.g. recent GEFS depicts
less than 20% probability for SCP values above 3). This suggests
that even though some severe threat will likely materialize,
considerable uncertainty remains regarding the quality of the
convective environment.

...D5/Wednesday and D6/Thursday...
Tuesday's cold front is expected to stall roughly along or south of
the OH River by the afternoon of D5/Wednesday. This will maintain a
moist warm sector across the southern Plains eastward to the TN
Valley. Strong to severe thunderstorm potential may emerge on
D5/Wednesday and D6/Thursday as an upper disturbance propagates
across the southern Plains and into the OH Valley and supports
ascent along and north of the stalled frontal zone. Given the
relatively focused nature of the wave and attendant mid-level jet,
widespread severe convection seems improbable, though a favorable buoyancy/shear environment is possible in the vicinity of the
stalled front each afternoon.

..Moore.. 03/28/2026

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ACUS48 KWNS 290846
SWOD48
SPC AC 290845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CDT Sun Mar 29 2026

Valid 011200Z - 061200Z

...DISCUSSION...
A more seasonal synoptic regime is expected over the CONUS through
the upcoming week as long-wave troughing slowly becomes established
over the western two-thirds of the country. This will favor lee
cyclone development and poleward moisture return ahead of occasional
frontal intrusions. In general, ensemble consensus is that a
leading, low-amplitude upper disturbance will propagate across the
central CONUS during the D4/Wednesday to D5/Thursday period before a
more amplified upper trough migrates into the Plains during the
D6/Friday to D7/Saturday time frame. While there is broad agreement
in this pattern among most guidance, notable discrepancies and
spread among solutions limits confidence in the location, timing, or
magnitude of any severe threat.

...D4/Wednesday - Southern Plains...
A cold front pushing east/southeast across the central U.S. on
Tuesday is forecast to stall across the southern Plains into the OH
Valley by Wednesday. Aloft, ascent associated with the leading upper disturbance will overspread TX/OK, leading to modest surface low
development along the stalled frontal boundary. Continued moisture
return coupled with easterly advection of steep mid-level lapse
rates will likely yield a reservoir of buoyancy across portions of central/eastern TX/OK and into AR/LA. Thunderstorm development along
the frontal zone appears probable by late afternoon, and 40-50 knot
mid-level flow attendant to the wave should provide adequate wind
shear for organized storms. However, guidance continues to show
variability with frontal placement and is likely displaying a
northward bias given the tendency for long-range guidance to
underestimate low-level cold advection. Additionally, it is unclear
whether storm motions and deep-layer shear vectors will be favorably
oriented to the front to support discrete convection and a more
robust severe threat.

...D6/Friday and D7/Saturday - Southern Plains to the Ohio Valley...
More intense surface low development is anticipated across the
southern Plains and Great Lakes region Friday into Saturday as an
more amplified upper wave begins to migrate east. Northward moisture
return will likely continue through Friday with thunderstorm
development possible in vicinity to the deepening lee cyclone.
Although model variability remains fairly high at this range,
ensemble guidance does show a modest QPF signal across OK/KS where
the probability for adequate SBCAPE and deep-layer shear for
organized convection is reasonably high.

On Saturday, the ejection of the upper wave into the Plains will
result in the northeastward acceleration of the lee cyclone. Rapid
moisture return within a strengthening low-level wind field is
possible as the low reaches the Great Lakes region by late Saturday.
Based on forecast soundings and ensemble QPF signals, some severe
thunderstorm potential is noted along and ahead of a cold front
attendant to the low. However, high variability among guidance over
the past 24 hours and the potential for a sub-optimal displacement
of the primary upper jet with the expanding warm sector casts
considerable uncertainty on the overall severe threat.

..Moore.. 03/29/2026

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ACUS48 KWNS 300855
SWOD48
SPC AC 300853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Mon Mar 30 2026

Valid 021200Z - 071200Z

...DISCUSSION...
Severe thunderstorm potential is expected to persist through the
work week and into the upcoming weekend. Long-range guidance has
come into better agreement over the past 24 hours regarding the
evolution of the synoptic regime - particularly regarding the
progression of an upper level trough and attendant surface low
during the late-week/early-weekend period.

...D4/Thursday - Midwest/Ohio Valley...
A cold front pushing across the Midwest on Tuesday is forecast to
stall across the OH Valley on Wednesday before advancing northward
as a warm front ahead of an approaching surface low on Thursday.
Northward moisture return is expected ahead of a weak cold front
attendant to the low. Long-range forecast guidance suggests this
will support adequate buoyancy for deep convection, and 35-45 knot
deep-layer shear vectors will favor organized storms. Uncertainties
regarding storm mode persist based on mean wind vectors largely
parallel to the front, but some severe risk appears likely given
favorable buoyancy and shear.

...D5/Friday - Central/Southern Plains...
Ensemble consensus is that an amplified upper trough will begin to
approach the central Rockies/High Plains through the day Friday.
This will promote strong lee cyclogenesis across CO/KS and a
northward surge of moisture (potentially as high as low to mid 60s
dewpoints) into OK and eastern KS. Thunderstorm development in
proximity to the deepening low appears probable by late afternoon
based on deterministic and ensemble QPF signals, and strengthening
flow aloft may favor discrete storm modes for convection developing
along a sharpening dryline. Ensemble guidance, notably the 00z GEFS,
shows a fairly strong signal for a substantial convective
environment from northern OK into eastern KS Friday afternoon (e.g.
30% probability for SCP values above 5). Despite improving agreement
among deterministic and ensemble guidance, this alignment has only
emerged over the past 12-24 hours. Severe probabilities will likely
be needed for portions of eastern KS and northern OK if this trend
holds over the next 24 hours.

...D6/Saturday - Ohio Valley...
Similar to D5/Friday, guidance has come into better agreement
regarding the intensification and northeastward progression of the
surface low through D6/Saturday into the Great Lakes region. This
will usher moisture northward into the OH Valley by Saturday
afternoon where diurnal heating may support either development of
new convection along a trailing cold front and/or re-intensification
of residual convection (though the quality and extent of moisture
return remains somewhat uncertain at this range). Regardless,
intensifying wind fields should promote storm organization and the
potential for a more widespread severe weather event. As with
D5/Friday, risk probabilities will likely be needed if current model
trends are maintained and confidence the moisture/buoyancy quality
increases.

..Moore.. 03/30/2026

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ACUS48 KWNS 310852
SWOD48
SPC AC 310850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Tue Mar 31 2026

Valid 031200Z - 081200Z

...DISCUSSION...
Severe weather potential will persist through the remainder of the
work week and into parts of the weekend as an amplified upper wave
and attendant surface low traverse the country. The cold front
associated with the late-week storm system will most likely push
south into the Gulf by Sunday as high pressure builds across the
eastern two-thirds of the country and short-wave ridging builds
aloft. This will likely limit the potential for widespread severe
thunderstorms for the early portion of next week.

...D4/Friday - Lower Missouri Valley into the southern Plains...
The approach of an upper wave into the central U.S. will support
steady intensification of a surface low across eastern KS and into
the lower MO River Valley through the day Friday. This will support
a northward flux of low to mid 60s dewpoints through the day, which
should yield SBCAPE values on the order of 2000 to perhaps 3000 J/kg
across northern OK into eastern KS and far western MO by late
afternoon based on a consensus of model solutions. Thunderstorm
development is expected as a cold front slowly begins to push
southeast and overtakes a surface trough/dryline. Deep-layer shear
vectors and storm motions off the boundary should promote initially
discrete cells, though upscale growth is anticipated by the evening
hours amid persistent ascent along the front. Regardless, long-range
guidance has shown a consistent signal for a robust convective
environment over the past 48 hours, and the favorable alignment of
both deterministic and ensemble guidance lends high confidence in a
severe threat emerging across this region Friday afternoon and
evening.

...D5/Saturday - Midwest/OH Valley...
Friday's surface low will continue to deepen as it accelerates
northeastward into the Midwest and Great Lakes by late Saturday.
Northward moisture advection is expected ahead of a trailing cold
front as it rapidly shifts east across the Midwest and lower OH
Valley through the afternoon. Strong flow fields within the lowest
few kilometers and focused lift along the front will likely support
some degree of a severe wind threat. However, guidance continues to
show disagreement regarding mean wind vector orientation with the
front and the degree of pre-frontal destabilization, both of which
will influence the intensity of convection and the overall severe
threat.

..Moore.. 03/31/2026

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ACUS48 KWNS 010829
SWOD48
SPC AC 010827

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0327 AM CDT Wed Apr 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
Some degree of severe thunderstorm potential is expected to persist
through the upcoming weekend across portions of the Great Lakes/OH
Valley and possibly across the Mid-Atlantic. Heading into next week,
a combination of building surface high pressure behind a synoptic
cold front and the re-establishment of an upper ridge over the West
will limit severe weather chances.

...D4/Saturday - Great Lakes/OH Valley...
An upper wave and attendant surface low are forecast to quickly
translate from the Plains into the Great Lakes region late Friday
through Saturday. Moisture return immediately ahead of a trailing
cold front will likely support some degree of destabilization
Saturday afternoon across the Great Lakes/OH Valley; however,
long-range ensemble guidance does not show high probability in surface/mixed-layer buoyancy values exceeding 1000 J/kg.
Nonetheless, strong flow within the lowest 1-2 km will likely
support a severe wind threat with any convection that can become
sufficiently intense. While some severe risk is anticipated, the
combination of a modest thermodynamic environment and disagreement
regarding the timing/progression of the front through peak heating
precludes risk probabilities.

...D5/Sunday - Mid-Atlantic...
The synoptic cold front is forecast to push off the East Coast by
late Sunday, though long-range guidance shows disagreement regarding
the timing of the front. Slower solutions, such as the 00z ECMWF,
suggest that the frontal passage may occur during the afternoon
hours when diurnal destabilization will be greatest. Strong
low-level flow coupled with robust broad-scale ascent ahead of the
primary upper wave may support a band of strong to severe
thunderstorms. However, the general consensus among guidance at this
time is that this scenario is likely the outlier solution.

..Moore.. 04/01/2026

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ACUS48 KWNS 020835
SWOD48
SPC AC 020833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CDT Thu Apr 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
Severe weather potential will be limited for late weekend and into
the upcoming work week based on trends in latest guidance. A strong
synoptic cold front is forecast to push from the Appalachians and
lower MS Valley east/southeastward towards the East Coast and
northern Gulf through the day Sunday. While some severe threat may
materialize across the Carolinas and Mid-Atlantic Sunday afternoon,
it will be conditional on favorable timing of the frontal passage
with the diurnal heating maximum. The frontal passage will shunt
appreciable low-level moisture offshore by early Monday. Building
surface high pressure over the central to eastern CONUS through
early week will maintain dry and stable conditions east of the
Rockies. Additionally, the amplification of an upper ridge over the
West will limit thunderstorm chances across the Intermountain West.
This synoptic regime will limit moisture return back into the Plains
with most guidance suggesting that appreciable moisture return (55+
dewpoints) may not return to the Plains until the D8/Thursday time
frame. Consequently, the potential for severe convection will be
limited through at least the middle of the upcoming week.

..Moore.. 04/02/2026

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ACUS48 KWNS 030822
SWOD48
SPC AC 030821

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0321 AM CDT Fri Apr 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
From Monday to Wednesday, a relatively dry and cool airmass is
forecast to settle in across the continental U.S. For this reason,
thunderstorm potential will be low over most of the nation.

...Thursday/Day 7 to Friday/Day 8...
A large area of surface high pressure is forecast to move eastward
in the western Atlantic by Thursday, as moisture return takes place
into the south-central states. Scattered thunderstorm development
will be possible during the day from the southern and central Plains
eastward into the lower to mid Mississippi Valley. A chance for
thunderstorms will continue into Friday over the same general area
as moisture advection continues. An isolated severe threat will be
possible each afternoon and evening, but the confidence in the
spatial distribution regarding any potential threat is low at this
time.

..Broyles.. 04/03/2026

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ACUS48 KWNS 040846
SWOD48
SPC AC 040844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Sat Apr 04 2026

Valid 071200Z - 121200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
A large area of surface high pressure will settle in across the
continental U.S. on Tuesday and Wednesday. The associated dry and
cool airmass will limit thunderstorm potential in most areas.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, a cold front is forecast to move southward into the
central Plains and stall, as moisture advection takes place to the
south of the front over much of the southern Plains. A dryline is
forecast to setup over west Texas Thursday afternoon. Thunderstorm
development will be likely along parts of the front and to the east
of the dryline. An isolated severe threat will be possible in the
afternoon and evening. Models differ considerably on the
distribution of instability, with some suggesting that instability
will remain relatively weak. This would keep any severe threat
marginal in most areas.

On Friday and Saturday, a moist and unstable airmass is forecast to
be in place over the southern half of Texas, as a shortwave trough
moves northeastward across the region. Lift associated with this
feature would support scattered thunderstorm development. The
greatest severe potential both Friday and Saturday appears to be
across south-central Texas, where the models have moderate
deep-layer shear and sufficient instability. At this extended range, uncertainty concerning magnitude and spacing is substantial.

..Broyles.. 04/04/2026

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ACUS48 KWNS 050850
SWOD48
SPC AC 050848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Sun Apr 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
...Wednesday/Day 4 and Thursday/Day 5...
From Wednesday into Thursday, an upper-level trough will move from
the High Plains into the Great Lakes, as a large area of surface
high pressure moves across the eastern U.S. Along the western edge
of this feature on Thursday, low-level moisture advection is
forecast from the southern and central Plains into the lower to mid
Mississippi Valley. Within this returning airmass, isolated to
scattered thunderstorms will be possible Thursday afternoon and
evening. The best chance for severe storms would be across parts of
the central Plains, as the low-level jet ramps up in the evening.
Uncertainty exists concerning the magnitude of any potential severe
threat.

...Friday/Day 6 to Sunday/Day 8...
Moisture advection is forecast to continue on Friday over the
southern Plains and Ark-La-Tex, as surface dewpoints increase into
the 60s F. A slow-moving cold front is forecast to stall in the
central Plains, which would be a focus for thunderstorm development.
Isolated to scattered storms are also expected on Friday along and
to the east of a dryline in the southern High Plains. An isolated
severe threat would be possible in areas that sufficiently
destabilize. The potential for severe storms should continue into
Saturday and Sunday over the southern and central Plains, as an
upper-level trough moves across the region. At this time, model
spread is substantial concerning the magnitude and spatial
distribution of instability. The models also vary widely on the
timing and amplitude of the shortwave trough. For these reasons,
will hold off introducing a threat area until the models can show
better agreement.

..Broyles.. 04/05/2026

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ACUS48 KWNS 060835
SWOD48
SPC AC 060834

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0334 AM CDT Mon Apr 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
From Thursday to Saturday, mid-level flow over the south-central
U.S. is forecast to gradually transition from westerly to
southwesterly. In response, low-level moisture advection will likely
take place in the southern and central Plains. Isolated severe
storms will be possible near a front in the central Plains from late
Thursday afternoon into the early overnight period, as a low-level
jet strengthens. On Friday, weak instability is forecast to develop
over much of the southern Plains. Isolated to scattered
thunderstorms will be possible in the afternoon and evening across
parts of this airmass. An isolated severe threat may develop in some
areas, but deep-layer shear is forecast to be relatively weak over
much of the southern Plains, suggesting a more localized severe
potential.

On Saturday, the potential for severe storms is expected to increase
over parts of southern High Plains, as mid-level southwesterly flow strengthens. Model consensus suggests that the greatest severe
threat potential will be over parts of west Texas, where some models
have an axis of moderate instability in place by late Saturday
afternoon. Supercells with large hail and severe wind gusts will be
possible in the afternoon and evening, with storms that develop near
this instability axis.

...Sunday/Day 7 and Monday/Day 8...
On Sunday, an upper-level low and an associated trough is forecast
to move eastward across the Desert Southwest and northern Mexico.
Ahead of this trough, moderate instability is forecast to develop by
Sunday afternoon over much of the southern High Plains. Scattered
severe storms would be possible to the east of a west Texas dryline
in the afternoon and evening. A severe threat should continue into
the overnight as a low-level jet strengthens ahead of the
approaching trough.

On Monday, the upper-level trough is forecast to move quickly
northeastward across the central U.S, with an axis of moisture and
instability located in the Great Plains. Scattered severe storms
will be possible from Monday into Monday night from the southern
Plains northward into Upper Midwest. At this extended range, there
is still considerable uncertainty concerning the timing of the
trough. For this reason, will hold off on a threat area until the
models show better agreement.

..Broyles.. 04/06/2026

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