MD 0461 CONCERNING SEVERE POTENTIAL…SEVERE THUNDERSTORM WATCH LIKELY FOR SOUTHEAST MINNESOTA…NORTHEAST IOWA…SOUTHWESTERN WISCONSIN
Mesoscale Discussion 0461 NWS Storm Prediction Center Norman OK 0534 PM CDT Tue Apr 04 2023 Areas affected...Southeast Minnesota...Northeast Iowa...Southwestern Wisconsin Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 042234Z - 050000Z Probability of Watch Issuance...80 percent SUMMARY...Severe thunderstorm watch will likely be warranted in the next one to two hours to account for expected increase in robust thunderstorms across the upper Mississippi Valley. DISCUSSION...Strong low-level warm advection remains focused across the upper MS Valley early this evening. Warming/moistening near 850mb is contributing to an increasingly buoyant profile atop very cool boundary layer north of the front. Forecast soundings exhibit very steep mid-level lapse rates with latest NAM suggesting upwards of 3000 J/kg MUCAPE if lifting a parcel near 850mb. Latest thinking is elevated convection will begin to develop across northeast IA then spread/develop downstream. Large hail should occur with the strongest convection and this warrants a severe thunderstorm watch. ..Thompson/Darrow.. 04/04/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...MKX...ARX...MPX...DMX... LAT...LON 44449324 44228932 42668921 42709356 44449324
