Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Oct 22 2025 08:47:00 ACUS48 KWNS 220846 SWOD48 SPC AC 220845 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0345 AM CDT Wed Oct 22 2025 Valid 251200Z - 301200Z ....DISCUSSION... ....D4/Sat-D5/Sun East TX/Lower MS Valley... The upper low over the southern Plains will shift eastward this weekend, gradually wakening as it moves over the lower MS Valley. This should result in a rather nebulous surface pattern, with broad low-level warm air advection expected over much of eastern TX and the lower MS Valley. The environment will likely remain supportive of scattered thunderstorms and isolated severe potential given sufficient buoyancy and moderate flow aloft. However, confidence in specific hazards or storm mode is low. ....D6/Monday Plains and MS Valley... To the west of the departing upper low, a second Pacific trough will move onshore over the Northwest late this weekend before intensifying early next week. As the main trough and several small-scale perturbations within enhanced westerly flow aloft cross the Rockies, a surface low may develop over the Plains potentially allowing for some northward return of moisture coincident with increased vertical shear. This could support thunderstorms and some severe risk across the eastern Plains and Mid/Lower MS Valley. Model guidance remains highly varied on the evolution of this system with the GEFS/GFS notable outliers in its intensity among other solutions. Guidance has trended toward an overall less amplified and more disjointed evolution, with persistent mid-level troughing over the eastern US. This would likely suppress northward return moisture and any potential warm sector over the Plains and Mid MS Valley. Still, some severe risk remains possible over the southern Plains and lower MS valley early next week given the increase in surface moisture and flow aloft. However, the evolution and potential hazards remains very uncertain. ...Lyons.. 10/22/2025 = = = 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) .