Mesoscale Discussion 0991

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000 ACUS11 KWNS 052224 SWOMCD SPC MCD 052224 MIZ000-WIZ000-060030- Mesoscale Discussion 0991 NWS Storm Prediction Center Norman OK 0524 PM CDT Fri Jun 05 2026 Areas affected...Parts of central/northern WI and southern Upper MI Concerning...Severe Thunderstorm Watch 274... Valid 052224Z - 060030Z The severe weather threat for Severe Thunderstorm Watch 274 continues. SUMMARY...A threat for locally damaging wind and isolated hail may spread east-southeastward into the early evening. DISCUSSION...A cluster of occasionally strong storms is ongoing at 2215 UTC across parts of northwest WI. MLCAPE of 1000-1500 J/kg and effective shear of 30-35 kt are marginally supportive of organized convection, though relatively weak midlevel lapse rates and low-level flow have hindered potential for a more substantial severe threat thus far. With time, expanding outflow within a steep low-level lapse rate environment could support an increasing threat for damaging wind as convection moves east-southeastward, and isolated hail cannot be ruled out with the strongest embedded updrafts. An isolated severe threat will spread to the north and east of WW 274 into early evening. The need for a new watch is uncertain given current trends, but these storms will be monitored for an uptick in storm organization through 00 UTC. ..Dean/Gleason.. 06/05/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MQT...GRB...MKX...DLH...ARX...MPX... LAT...LON 46128990 46298865 46198805 46088782 45938764 45808757 45438765 45238772 45148777 44638820 43888891 43718978 43929106 44179168 44419196 44599232 44819138 45409040 46128990 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN