Storm Prediction Center Mesoscale Discussion 1403

   Mesoscale Discussion 1403
   NWS Storm Prediction Center Norman OK
   0533 PM CDT Tue Jun 30 2026

   Areas affected...portions of eastern Wisconsin and the southern
   Upper Peninsula of Michigan

   Concerning...Severe Thunderstorm Watch 424...

   Valid 302233Z - 010000Z

   The severe weather threat for Severe Thunderstorm Watch 424
   continues.

   SUMMARY...Potential for primarily damaging wind gusts and large hail
   continues across portions of Severe Thunderstorm Watch 424,
   including eastern Wisconsin and southern portions of the Michigan
   Upper Peninsula.

   DISCUSSION...Isolated to widely scattered convection has developed
   along a weak surface boundary across portions of central/eastern
   Wisconsin over the past 1-2 hours and has produced isolated reports
   of small hail and damaging wind gusts. While effective shear remains
   generally modest (25-35 kts) and low-to-mid level temperatures
   remain relatively warm across the region, strong to extreme buoyancy
   (4000-5000 J/kg per latest objective analysis) is expected to
   continue to support strong to severe thunderstorms across this
   region for another several hours. In the near-term, convection may
   tend to remain discrete/semi-discrete with a greater threat for
   large hail owing to modestly steep mid-level lapse rates (7-7.5
   C/km). Some consolidation of cold pools over the next 1-2 hours may
   then foster upscale growth and a transition towards damaging wind
   gusts as the primary threat.

   ..Chalmers.. 06/30/2026

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

   ATTN...WFO...MQT...GRB...

   LAT...LON   44538724 44338748 44218787 44218831 44338865 44488882
               44698893 44868886 45268861 45648833 45948798 46028756
               45898704 45528688 45108695 44768706 44538724 

   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