Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Jun 22 2025 08:34:10 ACUS48 KWNS 220834 SWOD48 SPC AC 220832 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0332 AM CDT Sun Jun 22 2025 Valid 251200Z - 301200Z ....DISCUSSION... ....D4/Wednesday... Extended-range guidance generally indicates that the persistent upper ridge across the eastern CONUS will begin to dampen on Wednesday. Multiple low-amplitude midlevel shortwave troughs will move along the periphery of the upper ridge from the central/northern High Plains into the Great Lakes. Mid/upper-level flow will generally be rather weak, but may be locally stronger in the vicinity of any shortwave troughs. Some severe threat could develop where pockets of somewhat stronger flow overlap moderate to strong buoyancy along the periphery of the ridge. An MCS may develop late on D3/Tuesday and move across parts of the central Plains and Midwest into at least early Wednesday. This MCS could persist through the day, with additional development possible along an outflow-influenced front. Other strong to severe storms may again develop across parts of the central/northern High Plains. Confidence regarding the details of any organized severe threat is too low to delineate a 15% area at this time. ....D5/Thursday - D8/Sunday... Guidance generally suggests that the persistent upper ridge will continue to weaken with time, resulting in a more zonal pattern by the upcoming weekend. Stronger flow may become increasingly confined to the northern tier of states. This could lead to periodic severe threats across parts of the northern Plains into the Great Lakes and Northeast. One area of interest is across parts of the northern Plains Friday into Saturday. Some guidance takes a mid/upper-level shortwave trough from the Pacific Northwest into the northern Great Plains during this period, where it may impinge upon increasing low-level moisture and instability, resulting in potential for organized severe storms. ...Dean.. 06/22/2025 = = = 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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .