• MESO: Mesoscale Discussion 1729

    From COD Weather Processor @1:2320/107 to All on Sat Jul 25 19:15:46 2026
    ACUS11 KWNS 251915
    SWOMCD
    SPC MCD 251915
    SDZ000-NEZ000-252045-

    Mesoscale Discussion 1729
    NWS Storm Prediction Center Norman OK
    0215 PM CDT Sat Jul 25 2026

    Areas affected...south-central to southeast South Dakota

    Concerning...Severe potential...Watch likely

    Valid 251915Z - 252045Z

    Probability of Watch Issuance...95 percent

    SUMMARY...80-100 mph winds are possible this afternoon and evening
    from south-central to southeast South Dakota. A severe thunderstorm
    watch will be needed in the next 1 to 2 hours.

    DISCUSSION...A very hot environment is in place across South Dakota
    with temperatures of 105 to 110F across southwest and south-central
    South Dakota. The 18Z UNR RAOB shows nearly 2500 J/kg MLCAPE. This
    may be somewhat artificially inflated by the low-level dewpoint
    profile, but even after modifying this to something more realistic,
    MLCAPE near 2000 J/kg seems likely. This is significantly less than
    SPC mesoanalysis but is more congruent with current satellite and
    radar imagery which show what appears to be surface-based storm
    development within areas that currently indicate significant
    remaining inhibition from SPC mesoanalysis.

    These storms are developing on the leading edge of a mid-upper level
    cirrus deck as ascent associated with a weak shortwave trough
    emerges over the Plains. Expect these storms to continue to increase
    in coverage, and considering the 50F temperature/dewpoint spreads,
    expect outflow dominant storms and a congealing cold pool. There is
    some uncertainty how the storms will evolve, but given the
    environment with a hot and unstable airmass to the west and very
    high moisture content to the east with moderate shear and very steep
    lapse rates, expect an MCS to develop with the potential for intense
    wind gusts (perhaps has high as 100 mph).

    A severe thunderstorm watch will be needed for this threat in the
    next 1 to 2 hours and a PDS severe thunderstorm watch may be
    considered.

    ..Bentley/Smith.. 07/25/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!9sINd-3sG3D-9WEN-BYd1i2oJSfAvw7zp0OVX74OdSM_IbN3CdMRAYOa9K8ACrZbEf1j6VwpggxE62K2PDuYj_HrAJg$ for graphic product...

    ATTN...WFO...FSD...ABR...LBF...UNR...

    LAT...LON 44170221 44900061 45029856 44819662 43819654 43379694
    43039743 42990042 43050140 43580230 44170221

    MOST PROBABLE PEAK WIND GUST...85-100 MPH
    MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN


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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)