• Storm Prediction Center 15 07

    From LU9DCE@21:5/101 to ALERT on Mon Jul 15 04:10:13 2019
    __ _ _ ___ ____ ___ ____ ____ ____ ____
    ( ) / )( \/ _ \( \ / __)( __) ( _ \( _ \/ ___)
    / (_/\) \/ (\__ )) D (( (__ ) _) ) _ ( ) _ (\___ \
    \____/\____/(___/(____/ \___)(____) (____/(____/(____/
    ESTACION DE PACKET RADIO - BUENOS AIRES (GF05OM)
    BOLETINES INFORMATIVOS PROGRAMADOS (BIP)
    SLACKWARE LINUX - HELLOCODELINUX@GMAIL.COM

    +----------------------------------------------------------------------------+
    SPC 1200Z Day 1 Outlook
    Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258
    AM CDT Mon Jul 15 2019
    Valid 151200Z - 161200Z
    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF THE UPPER MIDWEST/GREAT LAKES AND CENTRAL/NORTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms capable of large hail, damaging
    wind, and perhaps a tornado or two will be possible this afternoon
    into this evening across portions of the Upper Midwest, Upper Great
    Lakes, and also the northern and central High Plains. Some tornado
    and damaging wind threat will persist with the remnants of Barry
    across the lower and mid Mississippi Valley.
    ...Upper Midwest/Upper Great Lakes... Convection may be ongoing
    at the start of the period this morning across portions of WI and
    the U.P of MI. Some rejuvenation of this activity is possible later
    today as it spreads into lower MI, where moderate instability/shear
    will support some threat for damaging wind and hail. Meanwhile,
    as a vigorous shortwave trough moves eastward across the southern
    Canadian Prairies, scattered thunderstorm development is possible
    across central/northern MN along a surface trough, and also across
    northern WI within a weakly capped environment, where a remnant
    outflow boundary may be left over from earlier convection. Moderate
    to strong instability and effective shear of 25-35 kt will support
    organized multicell clusters and perhaps a few supercells, with
    a corresponding threat of large hail and damaging wind. Low-level
    shear is forecast to remain relatively modest, but some conditional
    tornado threat will be present should any supercells develop,
    especially in the vicinity of any remnant outflow boundaries. Some
    upscale growth is possible into this evening, spreading a damaging
    wind threat into southern MN and central/southern WI.
    ...Northern Rockies into the northern/central High Plains...
    An upper trough will remain in place across the Northwest into the
    northern High Plains today. The timing of individual shortwaves
    moving through the mean trough position remains somewhat uncertain,
    but midlevel flow will remain sufficient to support effective
    shear of 40-50 kt. Given the potential for at least moderate
    destabilization, organized convection is expected to develop
    this afternoon, with initiation anticipated on the higher terrain
    before storms spread eastward. Organized clusters and perhaps a few
    supercells will be capable of large hail and damaging wind. Some
    upscale growth is possible into the evening, resulting in a severe
    wind threat spreading eastward into a larger part of western SD/NE. ...Lower/Mid Mississippi Valley... The remnant circulation of Barry
    should continue to weaken today, though some enhancement to low-level
    wind fields will persist across portions of the lower/mid Mississippi
    Valley. Midlevel lapse rates will remain poor across the region,
    but there is potential for at least some heating/destabilization
    later today. Shear will be sufficient to support a tornado or two
    and perhaps locally damaging wind gusts with the strongest convection
    east of the remnant circulation through much of the period.
    ..Dean/Squitieri.. 07/15/2019
    SPC 0600Z Day 2 Outlook
    Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1203
    AM CDT Mon Jul 15 2019
    Valid 161200Z - 171200Z
    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN
    HIGH PLAINS...
    ...SUMMARY... Isolated severe thunderstorms are possible across
    the northern High Plains with a few strong storms possible extending
    into the upper Mississippi Valley. Strong storms may also be noted
    with the remnants of Barry.
    ...Northern High Plains to the Upper MS Valley...
    Seasonally strong mid-high level flow is forecast to extend across
    the northwestern US-northern Plains-Great Lakes region into the
    day2 period. Latest data suggests remnants of late day1 convection
    that develops across the High Plains will progress into portions of
    eastern SD/NE by 16/12z. While a meaningful disturbance may not be
    noted with this activity, if an MCV evolves there is some concern
    strong convection could redevelop downstream across southern MN into
    WI by afternoon. Have extended 5% severe probs into the upper MS
    Valley to account for this possible scenario. If a well-defined MCV
    is evident at sunrise Tuesday, higher severe probs may be warranted.
    More confidence exists farther west regarding a notable short-wave
    trough that is forecast to progress into western MT-eastern ID
    by 17/00z. 60kt 500mb speed max is expected to translate across
    northern WY into southeast MT during the evening and this feature
    should encourage organized deep convection. Additionally, surface
    low is expected to develop over central WY during the afternoon
    which should maintain an easterly component to boundary-layer
    flow across the Plains into southern MT. Convection that develops
    off the higher terrain will likely grow upscale as it encounters
    higher-PW air mass and a more favorable LLJ that should strengthen
    after dark. Initial activity should be supercellular in nature
    with subsequent maturation and clustering expected to produce a
    possible MCS downstream over SD during the overnight hours.
    ...Remnants of Barry...
    Remnants of Barry are forecast to lift slowly north-northeast across
    AR into MO by Tuesday before shifting into the OH Valley mid week.
    Buoyancy will continue to be limited with this system as significant clouds/precip will prevent strong boundary-layer heating. Even
    so, veered LLJ is forecast to extend across northeast LA-western
    TN/KY-southern IN. There is some concern that a few weak supercells
    will develop along this corridor of stronger low-level shear. Will
    extend severe probs into the day2 period to account for a marginal
    tornado/wind threat.
    ...MAXIMUM RISK BY HAZARD... Tornado: 5% - Slight Wind:
    15% - Slight Hail: 15% - Slight
    ..Darrow.. 07/15/2019
    SPC 0730Z Day 3 Outlook
    Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0146
    AM CDT Mon Jul 15 2019
    Valid 171200Z - 181200Z
    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
    UPPER MS VALLEY AND NORTHERN HIGH PLAINS...
    ...SUMMARY... Some severe threat will exist with convection that
    develops across the upper Mississippi Valley and over the northern
    High Plains.
    ...Upper MS Valley...
    Seasonally strong mid-level speed max is forecast to translate across
    WY into the Dakotas early in the period before ejecting into MN by
    late Wednesday afternoon. An MCS is expected to evolve across the
    Dakotas late day2 and should be ongoing at sunrise along the nose
    of a LLJ that is expected to shift into southern MN later in the
    day. Much of this early-day activity should be elevated but outflow
    may ultimately dictate new development where boundary-layer heating
    is maximized. Will introduce 5% severe probs across the upper MS
    Valley to account for afternoon intensification along leading edge
    of expected MCS. This scenario is conditional and predicated on
    substantial convective overturning stabilizing much of northern
    MN. If thunderstorm activity is substantially weaker then severe
    probs may need to be extended to near the international border as
    large-scale forcing ahead of short-wave trough will extend into
    southern Canada.
    ...Northern High Plains...
    Trailing cold front will extend across central NE into central WY by
    late afternoon. Easterly boundary-layer flow should nudge higher-PW
    air mass across the High Plains toward the northern Laramie range.
    Strong surface heating across WY favors isolated thunderstorm
    development within a sheared regime supportive of supercells. This
    activity should spread toward the Black Hills by early evening.
    ..Darrow.. 07/15/2019
    SPC Day 1 Fire Weather Outlook
    Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK
    0109 AM CDT Mon Jul 15 2019
    Valid 151200Z - 161200Z
    ...Synopsis... A mid-level shortwave trough, traversing the
    Pacific Northwest, will gradually amplify across the northwest
    CONUS throughout the period. Stronger flow aloft associated with
    the mid-level shortwave trough may mix down to the surface via a
    deep boundary layer across far northern portions of the Great Basin
    into the northern Rockies region. As such, dry, breezy conditions
    may support wildfire spread potential in this area. Deep-layer
    ascent associated with the mid-level shortwave trough will also
    promote isolated to potentially scattered thunderstorm development,
    with a few dry strikes possible.
    Across central California, dry and breezy northerly surface flow
    will result from a pressure gradient, fostered by a surface high
    over the Sierra, across portions of the southern Coast Ranges late
    in the period.
    ...Far northern Great Basin into the northern Rockies... 15-20 mph
    sustained west-southwesterly surface winds will coincide with
    10-20% RH across portions of the Snake River Plain and Great Divine
    Basin by afternoon peak heating, where elevated delineations were
    maintained. In addition, potentially widespread elevated surface
    wind/RH conditions may also prevail across much of central Nevada,
    but the northward displacement of upper-level support renders
    low enough confidence to preclude an elevated area at this time,
    though an elevated delineation may be needed in later outlooks
    pending consistency in model guidance.
    As deep-layer ascent associated with the aforementioned mid-level
    shortwave trough overspreads a destabilizing air mass, isolated to
    potentially scattered thunderstorms will initiate across eastern
    portions of the Snake River Plain and along the windward side of the
    Absaroka and Wind River ranges with the aid of diurnal upslope flow.
    These storms will form atop a dry sub-cloud layer extending up
    to 500 mb, amidst 0.50-0.75 inch precipitable water values. Given
    adequate steering flow to promote faster moving storms, isolated
    dry strikes are possible, given that fuels have recently become
    marginally supportive of wildfire spread.
    ...Parts of southern California... Surface RH values of 10-20%
    will be common by late afternoon across portions of central
    California, with surface northerly winds expected to remain
    below elevated criteria across the San Joaquin Valley, given
    a modest pressure gradient in place. By early evening, locally
    stronger north-northeasterly offshore flow, (up to 20-30 mph)
    may become established in terrain favored areas of the Santa Ynez
    Mountains. While fuels will be somewhat marginal for fire spread,
    and despite the gradual recovery in RH expected through the evening,
    the stronger downslope winds may compensate to support a few hours
    of conditions favorable for fire spread, hence the maintenance of
    an elevated delineation in this area.
    ..Squitieri.. 07/15/2019
    ...Please see www.spc.noaa.gov/fire for graphic product...
    SPC Day 2 Fire Weather Outlook
    Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK
    0155 AM CDT Mon Jul 15 2019
    Valid 161200Z - 171200Z
    ...Synopsis... A mid-level shortwave trough will continue to
    gradually translate east/amplify across the western CONUS on
    Day 2/Tuesday. Stronger flow aloft will overspread a deeply-mixed
    boundary layer, which in turn will support dry and windy conditions
    across much of the Great Basin, where conditions will favor wildfire
    spread potential provided receptive fuels to fire spread.
    ...Great Basin... By afternoon peak heating, the stronger flow
    aloft will efficiently mix to the surface to sustain 15-25 mph west-southwesterly surface winds and 10-20% RH across much of the
    area. An elevated delineation was issued where the greatest overlap
    in elevated to critical surface wind/RH conditions and receptive
    fuels exists. Patchy receptive fuels, and recent accumulated rainfall
    from multiple days of scattered showers/thunderstorms serves as the
    primary mitigating factor for a critical delineation. Still, at least
    localized critical wind/RH conditions may be expected across much
    of southeast Nevada into far northwest Arizona and southwest Utah.
    Locally elevated conditions may also occur farther south into
    central Arizona, but the lack of upper-level support across this
    area to foster a more widespread 15+ mph wind field precludes an
    elevated delineation at this time.
    ...Far northern Great Basin into the northern Rockies... Deep-layer
    ascent associated with the mid-level shortwave trough will promote
    isolated to scattered thunderstorm development across much of the
    area. Currently, the latest model guidance suggests faster moving
    storms overspreading a deep sub-cloud layer may occur around the
    Idaho/Wyoming border. However, given marginally receptive fuels
    and recent accumulated rainfall, an isolated dry thunderstorm
    delineation has been withheld at this time.
    ..Squitieri.. 07/15/2019
    ...Please see www.spc.noaa.gov/fire for graphic product...

    +----------------------------------------------------------------------------+

    Since I hurt my pendulum My life is all erratic. My parrot, who was cordial, Is now transmitting static. The carpet died, a palm collapsed, The cat
    keeps doing poo. The only thing that keeps me sane Is talking to my shoe.
    -- My Shoe

    //////////////////////////////////////////////////////////////////////////////


    --- Mystic BBS v1.12 A43 (Linux/32)
    * Origin: HAMRADIO telnet lu9dce.dynu.com (21:5/101)