Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Sep 13 2025 17:30:29 ACUS02 KWNS 131730 SWODY2 SPC AC 131729 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Sat Sep 13 2025 Valid 141200Z - 151200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE NORTHERN PLAINS EXTENDING INTO THE SOUTHERN HIGH PLAINS... ....SUMMARY... Isolated severe storms are possible across parts of the northern Plains into the southern High Plains tomorrow (Sunday). ....Synopsis... A broad negative tilt trough will eject into the central Plains on Sunday, resulting in a deepening a surface low across the Dakotas. As the surface low deepens, the southerly low-level jet will increase with warm and moist advection from the southern Plains into the northern Plains. ....Great Plains States... The broad area of warm and moist advection will result in widespread shower/thunderstorm activity ongoing at the start of the period Sunday morning. In the wake of this morning convection, extensive cloud cover is expected to cover much of the region from the central Plains into the northern Plains. Some breaks in the cloud cover may allow for pockets of heating and recovery, but it remains uncertain how much air mass recovery will be achieved. Forecast soundings indicate tall skinny CAPE profiles and modest lapse rates (6-7 C/km) which may produce narrow updrafts that struggle to maintain intensity. Nonetheless, sufficient deep layer shear around 30-40 knots will support potential for a few organized storms to develop where recovery occurs, with development of multi-cell clusters and perhaps a few supercells. A narrow Marginal Risk was maintained across the Plains where redevelopment is most likely to start in the northern Plains and spread southward through the afternoon/evening. Closer to surface low across the Dakotas and on the nose of the low-level jet axis, a conditional risk for a tornado is possible if a supercell can be maintained. Overall, the main risks will be for sporadic strong to severe wind and hail. ...Thornton.. 09/13/2025 $$ = = = 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) .