SPC MD 390

MD 0390 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTHEASTERN MINNESOTA INTO FAR NORTHWESTERN WISCONSIN Mesoscale Discussion 0390 NWS Storm Prediction Center Norman OK 0303 PM CDT Sun Apr 12 2026 Areas affected...portions of northeastern Minnesota into far northwestern Wisconsin Concerning...Severe potential...Watch unlikely Valid 122003Z - 122200Z Probability of Watch Issuance...20 percent SUMMARY...A conditional hail/tornado threat will accompany any storm that develops and becomes sustained, though confidence in this scenario is currently low. DISCUSSION...A mid-level shortwave trough is currently overspreading the Upper MS Valley region, prompting the eastward progression of a surface low over northwestern Minnesota. Low-level moisture convergence (evident via 60+ F surface dewpoints) is occurring along the warm front ahead of the surface low (along a Cass to Carlton County, MN line), with a separate differential heating boundary noted from Cass to Pine Counties in MN. A cold front also extends from roughly Cass to Big Stone Counties. Ahead of the cold front, and in between the warm front and differential heating boundary, some increase in CU has been noted. Mesoanalysis shows 1000-1500 J/kg MLCAPE in place over this region, with CINH continuing to erode. Furthermore, mesoanalysis and RAP forecast soundings depict elongated mid-level hodographs with modest low-level curvature and over 40 kts of effective bulk shear. The ambient environment along the warm front supports supercell potential, accompanied by a hail and perhaps tornado threat should a storm develop. The main question is if convective initiation will occur given weak to modest deep-layer forcing for ascent. At the moment, thunderstorm development is uncertain. ..Squitieri/Mosier.. 04/12/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...MPX... LAT...LON 46019146 45889144 45759146 45659151 45519168 45409192 45349215 45449269 45679332 46019394 46289431 46679432 46899431 47079419 47139414 47189400 47169355 47009276 46809212 46349158 46019146 MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more