Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon May 26 2025 09:00:03 ACUS48 KWNS 260859 SWOD48 SPC AC 260858 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Mon May 26 2025 Valid 291200Z - 031200Z ....DISCUSSION... ....Thursday/Day 4 to Saturday/Day 6... A mid-level trough will move eastward into the eastern U.S. on Thursday, as a front remains over the Gulf Coast states and southern Plains. Thunderstorm development will be possible near and to the south of the front Thursday afternoon, with the greatest convective coverage expected over parts of east Texas and the lower Mississippi Valley. An isolated severe threat will be possible during the day on Thursday as surface heating takes place. Any severe threat should be concentrated in areas where low-level convergence becomes maximized near the front. At this time, confidence concerning a more focused severe threat area is low. On Friday, the front is forecast to move southward across the southern Plains and Gulf Coast states. Moderate instability is forecast to the south of the front across parts of south-central and southwest Texas, and across parts of Florida. Isolated to scattered thunderstorms may develop in these areas, with a marginal severe threat possible. On Saturday, northerly flow at mid-levels is forecast to develop over the Great Plains. In response, some models suggest surface high pressure will be dominant across the Great Plains. This would limit severe potential. However, other model solutions suggest that some low-level moisture could return northward into the southern Plains. If this occurs, isolated to scattered thunderstorms that develop in the afternoon could have a marginal severe threat. Predictability is low concerning any specific scenario. ....Sunday/Day 7 and Monday/Day 8... Northerly flow at mid-levels is forecast to remain over the Great Plains on Sunday, as a trough moves east-southeastward across the Gulf of America. At the surface, a large area of high pressure is forecast over the central and eastern U.S. Although isolated to scattered thunderstorms could form Sunday afternoon over parts of the Great Plains and Mississippi Valley, any severe threat is expected to be isolated. This same setup is forecast to continue into Monday. Further northwest into parts of the northern High Plains on Monday, model forecasts suggest a trough could move through the northern Rockies and approach the northern High Plains. An axis of moderate instability is forecast to develop by afternoon across parts of western South Dakota and eastern Montana, where a severe threat would be possible. However, predictability at this range is low. ...Broyles.. 05/26/2025 = = = 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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .