Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Sep 07 2025 16:57:29 ACUS02 KWNS 071657 SWODY2 SPC AC 071655 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1155 AM CDT Sun Sep 07 2025 Valid 081200Z - 091200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF WESTERN KANSAS...NORTHWEST OKLAHOMA AND THE OKLAHOMA/TEXAS PANHANDLES... ....SUMMARY... Isolated hail and damaging gusts are possible over portions of western Kansas, northwest Oklahoma and the Oklahoma/Texas Panhandles on Monday. ....KS/OK/TX... A northwest flow regime will persist over the Plains as the western upper ridge migrates east to the Rockies and a large-scale upper trough persists east of the MS River. A weak, convectively enhanced shortwave impulse will be located over KS Monday morning, shifting east toward the Lower MO Valley by evening. Convection will likely be ongoing across portions of central/eastern KS at the beginning of the forecast period and persist for much of the day. At the surface, a lee trough will extend north to south across the central/southern High Plains. Southerly low-level flow will transport low 60s F dewpoints northward across western OK and the TX/OK Panhandles into western KS beneath steepening midlevel lapse rates. Isolated thunderstorms may develop during peak heating within the narrow band of moisture near the surface trough. However, storm coverage and intensity remain uncertain given potential influence from outflow and cloud cover from the aforementioned convection across central/eastern KS. If storms can develop and become sustained, vertically veering/supercell wind profiles with elongated/straight hodographs will support large hail (and potentially some hail stones greater than 2 inches diameter). An upgrade to Slight risk (level 2 of 5) may be needed in subsequent outlooks if confidence in storm coverage and initiation location increases. ....NE to Upper Midwest... A surface trough will extend northeast across western/central NE into the Dakotas on Monday. Weak height falls are forecast in association with a minor shortwave trough develop southeast from the Canadian Prairies toward the international border. Southerly low-level flow will support 60s F dewpoints east of the surface trough and a narrow corridor of weak to moderate instability will develop during the late afternoon/early evening. Forecast soundings suggest capping, along with weak forcing, will limit diurnal thunderstorm activity. Warm advection and an increasing low level jet during the evening/overnight may support elevated storms across parts of northern MN/WI, but this activity is expected to remain sub-severe. If any storm can develop within the narrow warm sector, it could become strong, but overall severe potential is expected to remain low. ....Pacific Northwest... Scattered thunderstorms will develop as a low pressure system moves onshore Monday afternoon/evening. Moderate southwesterly flow will overspread a warm and weakly unstable airmass. Nevertheless, steep lapse rates and stronger mid-level flow could support sporadic strong gusts from high-based storms across central OR into southern WA. ...Leitman.. 09/07/2025 $$ = = = 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) .