Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
292 ACUS02 KWNS 251721 SWODY2 SPC AC 251719 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1219 PM CDT Sat Jul 25 2026 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID MISSOURI VALLEY ACROSS THE UPPER MISSISSIPPI VALLEY AND WESTERN GREAT LAKES... ...SUMMARY... Severe thunderstorms capable of large hail and damaging winds are possible from the upper Mississippi Valley and Great Lakes into portions of the mid Missouri Valley on Sunday and Sunday night. ...From eastern SD and NE to the Upper Great Lakes... The forecast continues to have major uncertainties regarding placement of the most likely severe storm corridors, with a wide range of model solutions. In general, the most likely threat areas include northern MN into WI and Upper MI, on the periphery of the upper ridge and where stronger winds aloft will exist coincident with strong instability, and from southeast SD into northeast NE within a super-heated surface trough. Beneath 40-50 kt midlevel northwesterlies, areas of strong instability will develop with relatively steep midlevel lapse rates and 70s F dewpoints, from parts of MN into WI. Models suggest various storm clusters are possible late in the day, and these would travel quickly southeastward with damaging wind and hail likely. Some severe activity could potentially push south of the Slight Risk area into more of northern IL, IN, and Lower MI. However, the instability gradient will be a limiting factor for eastward extent. Clusters of storms, possibly forming into a small MCS, are also expected where very hot temperatures develop into SD. The deeply mixed boundary layer combined with surface convergence within the low pressure trough will support afternoon development over eastern SD, with a corridor of damaging wind potential extending southeastward into eastern NE and western IA. ...SC and GA... Daytime heating of a high PWAT air mass will lead to moderate instability during the afternoon. A surface trough will deepen over the central Carolinas and into eastern GA, with an uncapped air mass and weak convergence yielding scattered storms. Shear will be weak, but modest northwest flow aloft should support corridors of damaging wind gusts as storms develop southeastward toward the coast. ..Jewell.. 07/25/2026 $$