• MESO: Mesoscale Discussion 1669

    From COD Weather Processor @1:2320/107 to All on Mon Jul 20 04:43:02 2026
    ACUS11 KWNS 200442
    SWOMCD
    SPC MCD 200442
    MNZ000-SDZ000-NDZ000-200545-

    Mesoscale Discussion 1669
    NWS Storm Prediction Center Norman OK
    1142 PM CDT Sun Jul 19 2026

    Areas affected...Eastern ND/northeast SD into west-central/northwest
    MN

    Concerning...Severe Thunderstorm Watch 499...

    Valid 200442Z - 200545Z

    The severe weather threat for Severe Thunderstorm Watch 499
    continues.

    SUMMARY...A short-term threat for isolated severe hail/wind may
    spread across far northeast South Dakota into west-central
    Minnesota. Additional strong to severe storm development is possible
    into the overnight into eastern North Dakota and northwest
    Minnesota, though coverage and timing remains very uncertain.

    DISCUSSION...A persistent and occasionally severe storm cluster is
    approaching the northeast corner of SD as of 0440 UTC. In the short
    term, moderate elevated buoyancy and favorable effective shear (as
    observed earlier in the prefrontal 00Z soundings from BIS and ABR)
    will continue to support some severe wind/hail threat. Longevity of
    this cluster is uncertain due to increasing CINH and generally
    modest large-scale ascent, but some severe threat could accompany
    this cluster as it moves into west-central MN during the early
    overnight hours.

    Farther north, a conditionally favorable environment remains in
    place across eastern ND into far northwest MN, along/ahead of a cold
    front. Short-term guidance continues to vary considerably regarding
    the timing and coverage (if any) of elevated storm development in
    this area into the overnight hours. Should sustained storms develop
    within this region, MUCAPE of 2000-3000 J/kg and favorable
    deep-layer shear would support a threat for severe wind and hail.
    With generally weak ascent and only a modest low-level jet response anticipated, potential for more than isolated strong to severe storm development overnight remains very uncertain. However, watch
    issuance will become possible if trends support development of
    multiple severe storms.

    ..Dean/Hart.. 07/20/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!4Aod2NHIma1BDN7RQWQX63qr-k7p2SYKSymwtckDXZyFPcmAQ98zwE9dpJtSWNo_HzII_Yt4z6dcsTS97Z0mEqqkxVk$ for graphic product...

    ATTN...WFO...DLH...MPX...FGF...ABR...BIS...

    LAT...LON 45729560 44859765 44999818 45839955 46289982 46779932
    49029787 49119698 49329505 49189453 48579426 47909438
    45729560

    MOST PROBABLE PEAK WIND GUST...65-80 MPH
    MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN


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