• MESO: Mesoscale Discussion 0615

    From COD Weather Processor@1:2320/107 to wx-storm@lists.illinois.edu on Wed Apr 29 15:22:08 2026
    ACUS11 KWNS 291522
    SWOMCD
    SPC MCD 291521=20
    LAZ000-ARZ000-TXZ000-291715-

    Mesoscale Discussion 0615
    NWS Storm Prediction Center Norman OK
    1021 AM CDT Wed Apr 29 2026

    Areas affected...northeast Texas...far southwest Arkansas...and
    northwest Louisiana

    Concerning...Severe potential...Watch possible=20

    Valid 291521Z - 291715Z

    Probability of Watch Issuance...60 percent

    SUMMARY...Severe-weather potential is expected to increase across
    the discussion area this morning with the primary hazards being
    large to very large hail and damaging wind gusts. Convective trends
    are being monitored for a possible watch.

    DISCUSSION...A small cluster of elevated thunderstorms has persisted
    this morning in far northeast TX, west of Texarkana, with recent intensification noted in a couple of the cells. While forcing for
    ascent remains nebulous, the 12z FWD sounding sampled a weakly
    capped and strongly unstable environment (MUCAPE of 3000-3500 J/kg)
    for parcels lifted from around 850 mb. Moreover, the kinematic
    environment from that sounding featured an effective bulk shear
    magnitude of 60+ kt, more than supportive of supercell storm modes,
    especially given the strong buoyancy.

    A number of CAMs suggest the continued intensification of the
    ongoing storms into supercells by late morning or early afternoon
    with subsequent upscale growth into a surface-based line of storms
    as the activity crosses the surface cold front and roots in the very
    moist and unstable air mass south of the boundary. In that scenario,
    large to very large hail (2-3" in diameter) will be the primary
    hazard initially, with damaging wind gusts becoming more likely as
    storms become surface based, and a more organized cold pool can
    develop.

    Convective trends are being monitored for further storm
    intensification, which would necessitate a watch issuance.

    ..Mead.. 04/29/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-FqNfFCQGSbSlkfOPZYk1vd9xI71zFSMOYna-cwuU8cX3UPkzylfgyDUa-jFPLoUquLz-Mq2V= TAiy6qwDqDH3_6_dUs$ for graphic product...

    ATTN...WFO...SHV...FWD...

    LAT...LON 33319645 33769569 33519420 32679265 32239214 31709242
    31529311 31399369 31639434 32289576 32649628 33319645=20

    MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH
    MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN


    =3D =3D =3D
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    * Origin: Capitol City Online (1:2320/107)