Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Feb 25 2024 09:50:48 ACUS48 KWNS 250950 SWOD48 SPC AC 250949 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0349 AM CST Sun Feb 25 2024 Valid 281200Z - 041200Z ....DISCUSSION... ....Wednesday/Day 4... An upper-level trough is forecast to move into the Great Lakes and Ohio Valley on Wednesday, as a cold front sweeps quickly southeastward across the southern and central Appalachians. Instability ahead of the front is forecast to be very weak at the start of the period. Wednesday morning, scattered thunderstorms appear likely to be ongoing across parts of the Ohio Valley and southern Great Lakes, where a marginal severe threat is anticipated. As the cold front progresses southeastward during the day, additional storm development could take place near the front in parts of the lower Great Lakes and central Appalachians. Although a marginal wind-damage threat could occur along parts of the front, abundant cloud cover and very weak instability will likely limit any potential for severe storms Wednesday afternoon. Due to downward trends in the model forecasts concerning severe potential, the 15 percent area has been removed. ....Thursday/Day 5 to Sunday/Day 8... A large area of surface high pressure will likely move through the eastern U.S. from Thursday into Friday. Thunderstorms will be possible across parts of the central Gulf Coast on Friday, on the far northern edge of a moist airmass. As winds return to the south across the southern Plains, moisture advection is expected from late Friday into Saturday. An upper-level trough is forecast to develop in the western U.S., with winds remaining southwesterly across the central states over the weekend. The ECMWF is currently forecasting a corridor of instability to develop across the southern and central Plains on Sunday/Day 8, with an upper-level low moving into the central High Plains. This solution would suggest a severe threat across parts of the region Sunday afternoon and evening. However, the GFS solution is not in agreement with weaker moisture return and much less instability. At this point, a wide spread in model solutions suggests too much uncertainty is present to consider adding a severe threat area. ...Broyles.. 02/25/2024 = = = 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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .