• Heavy Rain/Flooding TX/OK

    From Mike Powell@618:250/1 to All on Sat Apr 26 09:46:00 2025
    AWUS01 KWNH 261015
    FFGMPD
    TXZ000-OKZ000-NMZ000-261500-

    Mesoscale Precipitation Discussion 0183
    NWS Weather Prediction Center College Park MD
    615 AM EDT Sat Apr 26 2025

    Areas affected...TX Panhandle into southwestern/central OK

    Concerning...Heavy rainfall...Flash flooding likely

    Valid 261013Z - 261500Z

    SUMMARY...Flash flooding is likely to continue across portions of
    the TX Panhandle into northwestern TX and southwestern OK over the
    next few hours. Peak rainfall rates of 2-3 in/hr and peak
    additional totals of 3 to 6 inches will be possible.

    DISCUSSION...Radar mosaic and infrared satellite imagery at 0945Z
    showed an MCS advancing slowly eastward across the TX Panhandle
    into southwestern OK. Embedded thunderstorms were located along
    and north of a wavy quasi-stationary front which extended westward
    across northern TX, just south of the Red River, into the southern
    TX Panhandle and eastern NM. A couple of forward propagating
    segments were observed toward the southeastern edge of the MCS (in
    the vicinity of Childress), located south of an eastward advancing
    MCV near Pampa. VAD wind plots showed 35 to 46 kt of southerly
    flow over west-central to central TX which backed to a
    southeasterly direction near the Red River, supporting the robust
    transport of low level moisture northward atop the surface front.

    The training and repeating nature of cells along and north of the
    front have supported peak rainfall rates of 2-3 in/hr across
    southern portions of the TX Panhandle within the unstable
    environment. The front marked the northern edge of 500-1500 J/kg
    MLCAPE with 1000+ J/kg MUCAPE located north of the front via the
    09Z SPC mesoanalysis.

    As the MCV over the TX Panhandle continues to advance eastward
    into western OK over the next few hours, continued convection
    enhanced through warm air advection will spread eastward beneath
    convectively influenced diffluent flow aloft. Meanwhile, scattered thunderstorms in the wake of the MCV over the western TX Panhandle
    are expected to continue to congeal as they advance eastward and
    eventually bow southeastward into the low level inflow layer with
    periods of training. Some of the heaviest rain is expected to
    occur south of the MCV track where new thunderstorm development
    ahead of the advancing southeastern flank of the MCS should setup
    a prolonged period of heavy rain with additional totals of 3 to 6
    inches possible through 16Z, most probable over portions of
    southwestern OK or perhaps far northwestern TX.

    Otto

    ATTN...WFO...ABQ...AMA...LUB...OUN...

    ATTN...RFC...ABRFC...WGRFC...NWC...

    LAT...LON 36249818 35819712 34999736 33889853 33659943
    33710086 33810202 34010268 34240320 34860353
    35430296 36000126

    $$
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  • From Mike Powell@618:250/1 to All on Wed Apr 30 08:00:00 2025
    AWUS01 KWNH 301246
    FFGMPD
    TXZ000-OKZ000-301500-

    Mesoscale Precipitation Discussion 0201
    NWS Weather Prediction Center College Park MD
    612 AM EDT Wed Apr 30 2025

    Areas affected...northwestern TX into central/northeastern OK

    Concerning...Heavy rainfall...Flash flooding likely

    Valid 301011Z - 301500Z

    SUMMARY...Scattered to numerous coverage of flash flooding is
    expected from portions of northwestern TX into central and
    northeastern OK through 15Z. Rainfall rates of 1-2 in/hr (locally
    higher) are likely to impact portions of the region which have
    recently received heavy rainfall, potentially leading to significant/considerable impacts.

    DISCUSSION...Radar imagery at 10Z showed a forward propagating
    line segment which extended from southwestern OK into northwestern
    TX, located along and north of a quasi-stationary front which
    draped southwestward from southern OK into the western Permian
    Basin of TX. Peak MRMS-derived hourly rainfall with the advancing
    line has generally been 1-2 inches. Over southern OK, a band of
    training resulted in 2 to 5 inches of rain from northern Wilbarger
    County, TX to Stephens County, OK, out ahead of the advancing line
    segment. In addition, immediately in the wake of the forward
    propagating line segment was an additional/small cluster between
    MAF and LBB, slowly advancing eastward.

    While some minor weakening of low level winds is expected over the
    next few hours with the diurnal cycle, 25-45 kt of flow at 850 mb
    is likely to maintain robust clusters of thunderstorms from
    northwestern TX into central/northeastern OK over the next 3-5
    hours. While line segments are expected to generally propagate
    toward the east, there will be instances of training within the
    line segments where orientation matches the SW to NE oriented
    deeper layer steering flow. Rainfall rates of 1-2 in/hr will be
    likely (locally higher) with an additional 2-4 inches through 15Z
    for portions of the region. Due to areas of ongoing flash flooding
    from recent heavy rainfall, scattered to numerous occurrences of
    flash flooding are expected and locally significant/considerable
    flooding could affect locations on either side of the Red River
    which have picked up 4+ inches of rain over the past 12 hours.

    Otto

    ATTN...WFO...FWD...LUB...MAF...OUN...SJT...TSA...

    ATTN...RFC...ABRFC...WGRFC...NWC...

    LAT...LON 36369678 35909572 35239553 34019604 32449740
    31839848 31689945 31680041 31910100 32160138
    32310186 32550216 32960214 33430166 33780050
    34809961 35819813

    $$
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  • From Mike Powell@618:250/1 to All on Sun Jun 8 14:12:00 2025
    AWUS01 KWNH 081807
    FFGMPD
    TXZ000-OKZ000-090005-

    Mesoscale Precipitation Discussion 0403
    NWS Weather Prediction Center College Park MD
    206 PM EDT Sun Jun 08 2025

    Areas affected...TX/OK Panhandles into Northwest TX and Southwest OK

    Concerning...Heavy rainfall...Flash flooding possible

    Valid 081805Z - 090005Z

    SUMMARY...Organizing supercell thunderstorms by mid-afternoon and
    gradual consolidation into a severe MCS by this evening may result
    in some scattered concerns for flash flooding where the cells to
    merge or locally train.

    DISCUSSION...The latest GOES-E GeoColor satellite imagery shows
    strong diurnal heating over the southern High Plains which is
    already favoring MLCAPE values as high as 2000 to 3000+ J/kg. A
    capping inversion which still remains in place will continue to
    steadily erode via additional surface heating over the next few hours.

    This will set the stage for well-organized and heavy showers and
    thunderstorms to develop near and to the south of a cold front
    dropping south toward the southern Plains, and also near and north
    of a retreating warm front situated farther south over western and
    northern TX. Already a northwest/southeast axis of elevated
    thunderstorms has developed over the last couple of hours over
    northwest TX given steep mid-level lapse rates.

    A highly sheared environment exists with effective bulk shear
    values of 30 to 50 kts in place, and these magnitudes are forecast
    to slowly increase through the afternoon hours. The combination of
    this and strong boundary layer instability will favor developing
    and expanding coverage of supercell thunderstorms by mid-afternoon.

    Aside from well-defined severe hazards, there will be a heavy
    rainfall component to the supercells considering the degree of low
    to mid-level moisture that is in place. The latest CIRA-ALPW data
    shows relatively enhanced moisture profiles from the surface up
    through the 700 mb level, and so many of the supercell
    thunderstorms will be capable of highly efficient rainfall rates
    that could reach 2 inches/hour.

    By early this evening, merging/consolidating supercell
    thunderstorms should lead the way for a severe MCS, but as this
    process occurs, there will be sufficient concerns for cell-mergers
    and cell-training such that some rainfall totals reach 2 to 4+ inches.

    This may result in concerns for scattered areas of flash flooding
    which will include some localized urban impacts.

    Orrison

    ATTN...WFO...AMA...LUB...OUN...

    ATTN...RFC...FWR...TUA...NWC...

    LAT...LON 36960058 36509954 35759881 35019838 34079832
    33409886 33490002 34210078 34820146 35690220
    36250233 36830196

    $$
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