Storm Prediction Center Mesoscale Discussion 1297

   Mesoscale Discussion 1297
   NWS Storm Prediction Center Norman OK
   0528 PM CDT Wed Jun 24 2026

   Areas affected...portions of the western Great Lakes region

   Concerning...Severe Thunderstorm Watch 387...

   Valid 242228Z - 250000Z

   The severe weather threat for Severe Thunderstorm Watch 387
   continues.

   SUMMARY...The risk for primarily large hail and damaging wind gusts
   continues across Severe Thunderstorm Watch 387. A brief tornado or
   two also remain possible.

   DISCUSSION...Regional radar imagery depicts widely scattered
   thunderstorms ongoing from northern Wisconsin southward into
   northern Illinois, with a mixed mode of supercells and clusters
   noted as of 2220 UTC. This convection has produced several reports
   of large hail (up to 1.25" in diameter) over the past 1-2 hours,
   with sporadic reports of wind damage and brief funnel clouds also
   received. This risk will persist over the next couple of hours as
   convection evolves east-southeastward towards Lake Michigan. 

   The greatest severe potential appears to exist across the southern
   half of the Severe Thunderstorm Watch area, where greater buoyancy
   exists within the hail growth zone, which may promote an instance or
   two of large hail approaching golf ball size. Modestly steeper
   low-level lapse rates will also continue to promote the potential
   for damaging wind gusts. Lastly, a brief tornado or two cannot be
   ruled out, especially where low-level SRH is modestly enhanced in
   the vicinity of the lake breeze.

   ..Chalmers.. 06/24/2026

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...MQT...GRB...LOT...MKX...DVN...DLH...ARX...

   LAT...LON   41858754 41708792 41628917 41758991 41889014 41989025
               42779068 43559071 44849050 44929046 45908958 46168843
               46138778 45798742 44658746 43248770 42078742 41858754 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN