• MESO: Mesoscale Discussion 1232

    From COD Weather Processor@1:2320/107 to wx-storm@lists.illinois.edu on Sunday, June 21, 2026 20:34:45
    ACUS11 KWNS 212034
    SWOMCD
    SPC MCD 212033=20
    NEZ000-KSZ000-COZ000-212230-

    Mesoscale Discussion 1232
    NWS Storm Prediction Center Norman OK
    0333 PM CDT Sun Jun 21 2026

    Areas affected...Eastern Colorado...southwest Nebraska...and
    northwest Kansas

    Concerning...Severe Thunderstorm Watch 364...

    Valid 212033Z - 212230Z

    The severe weather threat for Severe Thunderstorm Watch 364
    continues.

    SUMMARY...The threat for large hail continues across eastern
    Colorado and into southwest Nebraska. However, upscale growth into
    an MCS is anticipated through early evening with an attendant uptick
    in severe wind potential across northwest Kansas.

    DISCUSSION...Multiple instances of 1.0 to 1.75 inch hail have been
    noted across the central High Plains over the past couple of hours
    as loosely organized splitting supercells continue to develop and
    mature. Based on recent radar trends, these cells are likely
    sufficiently spaced to maintain mostly discrete storm modes for the
    next hour or two, which will maintain the threat for large hail -
    especially along/near the eastern CO border where thermodynamic
    conditions are most favorable for very large (2 inch) hail.=20

    Beyond the next couple of hours, the combination of deviant storm
    motions and colliding outflow boundaries (at least one of which is
    already noted in reflectivity data from KFTG) will promote storm
    interactions and gradual upscale growth into one or more clusters.
    As this occurs, cold pool amalgamation/intensification within an
    environment featuring steep low-level lapse rates should promote
    increasing potential for severe wind gusts, including occasional
    gusts upwards of 75 mph. Per time-lagged HRRR/RRFS ensembles, this
    transition appears most likely to occur across east-central CO and
    into northwest KS during the 22-00 UTC time frame.

    ..Moore.. 06/21/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!9Rmcjg7Oz1b4Zr5a7tHPs0hrmAQiQQZXpa1FAbBHPOAaep9EcqAI67ZSJfmJlRXwRg7CeP0AH= nqVro0aASjP-4chHKg$ for graphic product...

    ATTN...WFO...GID...LBF...GLD...PUB...BOU...CYS...

    LAT...LON 39040422 39320437 39570420 41360235 41620200 41670164
    41610122 40830006 40539992 40200000 39910028 38990125
    38690191 38570245 38530283 38530318 38590353 39040422=20

    MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
    MOST PROBABLE PEAK WIND GUST...65-80 MPH
    MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


    =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 3.28-Linux
    * Origin: Capitol City Online (1:2320/107)