• MESO: Mesoscale Discussion 0383

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Mon Apr 8 15:27:35 2024
    ACUS11 KWNS 081527
    SWOMCD
    SPC MCD 081526=20
    LAZ000-TXZ000-081800-

    Mesoscale Discussion 0383
    NWS Storm Prediction Center Norman OK
    1026 AM CDT Mon Apr 08 2024

    Areas affected...parts of the mid/upper Texas coastal plain and
    adjacent western Louisiana

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

    Valid 081526Z - 081800Z

    Probability of Watch Issuance...40 percent

    SUMMARY...Widely scattered strong thunderstorms may begin to form
    across and inland of mid/upper Texas and southwest Louisiana coastal
    areas by early afternoon. This may be accompanied by at least some
    risk for severe hail, and perhaps a tornado, before storms increase
    and intensify with a more notable increase in severe weather
    potential later this afternoon, as activity spreads toward
    central/northern Texas.

    DISCUSSION...An initial influx of low-level moisture, which
    accompanied a significant cyclone now weakening over the Upper
    Midwest vicinity, lingers along and south of a stalling/weakening
    boundary now extending across the lower Mississippi Valley into
    southeastern Texas. This includes surface dew points ranging from
    the lower 70s across the northwestern Gulf into immediate Texas Gulf
    coastal areas, and upper 60s F further inland across the coastal
    plain, which will begin to advect northwestward and northward
    through the day, downstream of a significant short wave trough
    turning eastward across the Southwest.

    Beneath the northeastern periphery of a plume of elevated
    mixed-layer air advecting across the lower Rio Grande Valley, this
    moisture already appears to be contributing to sizable CAPE on the
    order of 2000 J/kg. This probably will increase at least a bit
    further through the day, as thin spots and breaks in the overcast
    allow for some insolation.

    At the same time, models indicate strengthening of southwesterly
    flow into mid-levels (30-50+ kts in the 700-500 mb layer), beneath a
    strong upper jet emanating from the subtropical eastern Pacific, and
    by early afternoon the environment will become increasingly
    conducive to potential for supercells. Various model output
    suggests that at least widely scattered thunderstorms may begin to
    form across and inland of coastal areas by around 17-18Z, before
    gradually intensifying and increasing further within northwestward
    and northward spreading large-scale ascent aided by low-level warm
    advection.

    While it is possible that it may take a couple of hours for a more
    substantive increase in severe weather potential to develop, as
    storms acquire better inflow of more unstable near-surface air,
    initial storms may pose at least some risk for severe hail. The
    risk for a brief tornado may also not be completely negligible,
    though clockwise curved low-level hodographs will initially be weak.

    ..Kerr/Gleason.. 04/08/2024

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-jb4e4YE9_s1kLLDAgFCgEzdk_wUKNlL9D9jXrBLyoW7M9C9cayJ5U1TygOCaO2tLZaO4QynA= 9OEBPDRrFYTFxiA53s$ for graphic product...

    ATTN...WFO...LCH...SHV...HGX...CRP...EWX...

    LAT...LON 29189796 30279668 31559496 32079393 31989315 31709266
    30679286 30279415 29849513 29319588 28649711 28589781
    29189796=20


    =3D =3D =3D
    To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

    --- SBBSecho 3.20-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)