• DAY3 3/5 Risk Area Posted

    From Mike Powell@618:250/1 to All on Fri May 16 08:38:00 2025
    ACUS03 KWNS 160732
    SWODY3
    SPC AC 160731

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0231 AM CDT Fri May 16 2025

    Valid 181200Z - 191200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
    AND EASTERN KANSAS AND FAR NORTHERN OKLAHOMA...

    ...SUMMARY...
    Severe thunderstorms capable of all severe hazards are expected on
    Sunday across portions of the central and southern Plains.

    ...Synopsis...
    An upper-level trough will continue to amplify across the
    Intermountain West on Sunday with a leading mid-level shortwave
    trough forecast to emerge into the central Plains during the
    afternoon and evening. At the surface, a low 990s mb surface low is
    forecast to develop in the eastern Colorado/western Kansas vicinity.
    A dryline will extend south from this surface low with a warm front
    extending east into the Southeast.

    ...Central/Southern Plains...
    Low to mid 70s dewpoints will advect poleward east of a sharpening
    dryline across the central Plains Sunday morning/early afternoon.
    This, combined with strong heating, will result in strong to very
    strong instability across Oklahoma and into southern Kansas with
    moderate to strong instability across eastern Kansas. As a mid-level
    shortwave trough emerges over the Plains, inhibition will erode
    along the dryline with storm development possible during the
    afternoon. Deep layer shear will support supercells as the primary
    storm mode with potential for large hail. As the low-level jet
    strengthens through the day, the low-level hodographs will elongate
    and result in an increasing tornado threat, including the potential
    for strong tornadoes.

    Confidence in storm coverage is highest across Kansas near the
    triple point. While some uncertainty remains where the warm
    front/dryline intersection will be, it will likely be somewhere near
    central Kansas. An enhanced risk (Level 3 out of 5) has been added
    across Kansas and into northern Oklahoma where the confidence for
    storm coverage is highest. However, it is important to note that
    storms could be equally as intense within the slight risk area
    across Oklahoma as storm coverage concerns are the only limiting
    factor to higher severe weather probabilities at this time.

    ...Southeast...
    Isolated storms will be possible along the frontal zone from the Mid-Mississippi Valley to the Southeast. Moderate to strong
    instability and strong shear will be in place along the frontal
    zone. However, forcing should be weak, so storm coverage is
    uncertain at this time.

    ..Bentley.. 05/16/2025

    $$
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  • From Mike Powell@618:250/1 to All on Sat May 17 08:51:00 2025
    ACUS03 KWNS 170740
    SWODY3
    SPC AC 170739

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0239 AM CDT Sat May 17 2025

    Valid 191200Z - 201200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR NORTH
    TEXAS...MUCH OF EASTERN OKLAHOMA...EASTERN KANSAS...FAR NORTHWEST ARKANSAS...AND MUCH OF CENTRAL AND WESTERN MISSOURI...

    ...SUMMARY...
    Severe storms with all severe weather hazards are likely from
    portions of the Midwest to the southern Plains on Monday.

    ...Synopsis...
    A mid-level trough will move over the central/southern Plains on
    Monday. At the surface, an area of low pressure will move slowly
    east across Kansas and eventually into Missouri. A sharp dryline
    will extend from this surface low southward along the I-35 corridor
    into north-central Texas. A warm front will extend from this surface
    low southeastward into portions of the lower Ohio Valley and into
    the Carolinas Monday morning. This front will move slowly north
    through the day.

    ...Central/Southern Plains into the Midwest...
    Strong to very strong instability will develop across the Plains and
    into the Ozarks on Monday as temperatures warm into the 80s with
    dewpoints in the low 70s while mid-level temperatures cool ahead of
    the approaching mid-level trough. As strengthening mid-level flow
    overspreads the warm sector, a favorable environment for intense
    supercells will develop with 3000+ J/kg MLCAPE and 50+ knots of
    shear across a broad region. Large to very large hail will be likely
    within supercells across eastern Kansas and Oklahoma into northern
    Texas. The tornado threat remains potent but more uncertain. The
    weakening nature of the surface low and a strengthening low-level
    jet during the evening when mode remains less clear are the primary uncertainties at this time. Eventually expect storms to congeal into
    one or more MCSs with an increasing severe wind threat.

    Additional storms are likely late Monday evening as a cold front
    overtakes the dryline across Kansas and eventually into Oklahoma.
    Storm intensity during this period remains unclear as it will depend
    greatly on remaining instability in the wake of earlier convection.
    Regardless, if earlier convection does not materialize as expected,
    more robust storms are likely along the cold front. Therefore,
    between the likely dryline storms during the afternoon and potential
    for storms along the cold front Monday evening, numerous severe
    thunderstorms are likely across Kansas and Oklahoma with that threat
    continuing eastward into parts of Missouri and Arkansas Monday evening.

    ..Bentley.. 05/17/2025

    $$
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  • From Mike Powell@618:250/1 to All on Sun May 18 08:11:00 2025
    ACUS03 KWNS 180731
    SWODY3
    SPC AC 180730

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0230 AM CDT Sun May 18 2025

    Valid 201200Z - 211200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
    THE MID-MISSISSIPPI VALLEY...OHIO VALLEY...AND TENNESSEE VALLEY...

    ...SUMMARY...
    Severe thunderstorms are likely across portions of the Ohio Valley, Mid-Mississippi Valley, and Tennessee Valley on Monday.

    ...Synopsis...
    A mid-level low will stall and perhaps start to retrograde across
    parts of the Upper Midwest on Monday. A surface low in the MO/IL
    region will start to occlude during the day. A cold front will move
    east through the period with a warm front across the Ohio Valley.

    ...Mid-Mississippi Valley into the Ohio Valley and Tennessee Valley...

    Thunderstorms will likely be ongoing amid broad isentropic ascent
    and moderate elevated instability along the warm front in southern
    Illinois and Indiana and vicinity on Monday morning. South of this
    morning activity, where upper 60s to low 70s dewpoints are
    anticipated, moderate to strong instability is forecast to develop
    amid daytime heating. As 55 to 65 knots of mid-level flow
    overspreads the warm sector, strong shear will be present for
    supercells. Large to very large hail will be the primary threat
    initially, as low-level flow will likely be veered. However,
    low-level shear should be strong enough to support some tornado
    threat during the afternoon/evening. As storms grow upscale, one or
    more bowing segments may develop with an increased damaging wind
    threat during the evening and perhaps persisting into the overnight period.

    ..Bentley.. 05/18/2025

    $$
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