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  • MESO: Mesoscale Discussion 1679

    From COD Weather Processor @1:2320/107 to All on Mon Jul 20 23:18:08 2026
    ACUS11 KWNS 202317
    SWOMCD
    SPC MCD 202317
    MIZ000-210115-

    Mesoscale Discussion 1679
    NWS Storm Prediction Center Norman OK
    0617 PM CDT Mon Jul 20 2026

    Areas affected...eastern U.P. of Michigan and northern lower
    Michigan

    Concerning...Severe potential...Watch likely

    Valid 202317Z - 210115Z

    Probability of Watch Issuance...80 percent

    SUMMARY...Severe weather potential is expected to increase across
    the discussion area this evening with the primary hazards being
    damaging winds and large hail. A watch will likely be required prior
    to 01Z.

    DISCUSSION...Within the exit region of an upper-level jet streak
    advancing into WI, large-scale forcing for ascent will overspread
    the region from the west this evening. In response, a southwesterly
    low-level jet will strengthen from southern WI into lower MI, which
    in turn will enhance the flux of an increasingly moist and unstable
    air mass into the region from the west. That destabilization process
    will allow ongoing storms, including supercells, to spread southeast
    across Lake Michigan into northern lower MI later this evening.
    Inspection of forecast soundings suggests that storms may be
    slightly elevated atop a shallow, near-surface inversion, which may
    tend to mitigate a more robust tornado threat, despite strengthening
    low-level shear. Nonetheless, the presence of seasonably strong
    deep-layer shear will support the continuation of organized storm
    modes, including supercells and bowing structures, with the primary
    hazards being large hail and damaging wind gusts.

    ..Mead.. 07/20/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!5xsTrKJJlbo3Trtglxj5Xre8h4DdodYFRtJmuwxXtopyrl8LcExmmS9craVAsGmDSb-DBAPrUMYN984IU7BU_yhwjf0$ for graphic product...

    ATTN...WFO...APX...GRR...MQT...

    LAT...LON 44568687 45558617 46368511 46208385 45618344 45108332
    44558440 44048628 44168674 44568687

    MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH
    MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN


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