Mesoscale Discussion 1168 NWS Storm Prediction Center Norman OK 0445 PM CDT Wed Jun 17 2026 Areas affected...Northeast IA...southwest WI...extreme southeast MN Concerning...Severe Thunderstorm Watch 341... Valid 172145Z - 172345Z The severe weather threat for Severe Thunderstorm Watch 341 continues. SUMMARY...A threat for isolated hail, strong/damaging gusts, and possibly a tornado may spread southeast through late afternoon. DISCUSSION...A small thunderstorm cluster is moving across parts of extreme southeast MN and northeast IA late this afternoon, in the vicinity of a surface low and a seasonably strong mid/upper-level shortwave trough. Heating and destabilization have been relatively muted across this region, though MLCAPE increasing to near 1000 J/kg and moderate deep-layer shear will continue to support potential for organized storms through late afternoon. Isolated hail and strong/damaging gusts may accompany the strongest storms. Also, with low-level vorticity relatively maximized in the vicinity of the surface low, a tornado cannot be ruled out, especially if any sustained supercell structures can become established. This convection is approaching the southeast part of WW 341. Depending on short-term trends, local expansion of the watch may be considered, but the need for downstream watch issuance is uncertain, unless there is a notable uptick in storm intensity and organization. ..Dean/Smith.. 06/17/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...DMX... LAT...LON 44069244 43869098 43709069 43139049 42779051 42489051 42319079 42319131 42579200 42899237 43369268 43539268 44069244 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
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