Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Sep 10 2025 07:35:21 ACUS03 KWNS 100735 SWODY3 SPC AC 100734 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0234 AM CDT Wed Sep 10 2025 Valid 121200Z - 131200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Isolated storms are possible over parts of the Northern Plains and Upper Midwest with additional storms possible over the Rockies and Great Basin Friday. Severe potential is uncertain. ....Northern Plains and Upper Midwest... Shortwave ridging over the northern Plains and Upper Midwest is forecast to shift eastward Friday as weak troughing emerges from the Rockies. A modest increase in mid-level southwesterly flow will impinge upon rich low-level moisture near a weakening surface low and stalled warm front across the Dakotas and western MN. Low-level convergence near the low/front may serve as a focus for isolated thunderstorm development Friday afternoon and evening. Moderate MLCAPE around 2000 J/kg and steepening mid-level lapse rates could support a few stronger storms. Some enhancement of the mid-level flow may allow for a few storms to organize with some clustering and isolated strong outflow gusts. The primary uncertainty remains storm coverage with most guidance showing only sporadic convection through much of the day. An increase in convective coverage is possible overnight and into early Saturday as a 35-40 kt southerly low-level jet develops across the central Plains, bolstering low-level warm advection. Should this occur, one or more clusters of thunderstorms could propagate eastward along the warm front, potentially posing a risk for severe gusts. However, this is highly uncertain and with substantial model differences evident, no severe probabilities will be introduced. ....Intermountain West... Monsoon moisture is expected to linger over portions of the eastern Great Basin and central Rockies Friday ahead of a broad upper low. A shortwave trough within the southwesterly flow aloft will overspread the region near peak heating. The increase in ascent will support scattered thunderstorms over portions of the Intermountain West Friday afternoon and evening. While buoyancy will not be overly large (~500 J/kg of MLCAPE) and some remnant cloud cover/convection could overturn the air mass, increasingly strong southwesterly flow aloft could support a few stronger thunderstorms/clusters. With a fairly dry air mass in place, stronger downdrafts could be capable of isolated gusty winds given steep low-level lapse rates. ...Lyons.. 09/10/2025 $$ = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .