Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat May 31 2025 19:29:03 ACUS03 KWNS 311928 SWODY3 SPC AC 311927 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Sat May 31 2025 Valid 021200Z - 031200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL AND NORTHERN PLAINS... ....SUMMARY... Scattered severe thunderstorms are possible from far western Minnesota to the central High Plains from late afternoon to evening Monday. Isolated severe thunderstorms are possible across a broader portion of the central states from northern Minnesota to western Texas. ....Synopsis... A long-wave trough/ridge wave will continue to shift east across the central CONUS over the next 72 hours. By Monday afternoon, the primary ridge axis will shift across the lower MS River Valley/Midwest with a mean southwesterly flow regime across the Rockies/Plains. A pair of embedded shortwave trough, one moving along the U.S./Canadian border and another emanating out of the Southwest, will migrate into the Plains through early Tuesday. At the surface, a cold front trailing from a low cyclone over the Canadian Prairies will push into the northern/central Plains while a dryline sharpens along the High Plains. Severe thunderstorm chances will be focused along these boundaries as convection develops by late afternoon. ....Central and northern Plains... The deepening of the surface low over the Canadian Prairies will aid in moisture return into the Plains through the day Monday. Most guidance suggests dewpoints should reach into the low to mid 60s with MLCAPE values approaching 2000 J/kg as the front begins to impinge on the developing warm sector by late afternoon. While the strongest mid-level flow will remain displaced to the northwest of the front/warm sector, 25-35 knot winds will likely support adequate wind shear for organized convection. Initially discrete cells may pose a large hail threat, though weak off-boundary storm motions/deep-layer shear vectors and strong frontal forcing will likely promote relatively quick upscale growth into clusters/line segments. A strengthening nocturnal jet may promote southeastward propagation of clusters/lines into the evening hours across eastern SD and central/eastern NE with an attendant severe wind threat. ....Central to southern High Plains... Medium and long-range guidance nearly universally show some form of a QPF signal along the lee trough/dryline by 00 UTC Tuesday across southwest KS into western TX as a low-amplitude upper disturbance ejects into the Plains and lifts/erodes lingering capping. Sufficient buoyancy for robust convection will be in place across much of the High Plains east of the dryline (and should exceed 2000 J/kg based on the typically-dry GFS forecasts), but forecast hodographs show only modest elongation of the low to mid-level wind profile owing to somewhat mundane mid-level flow (generally between 15-30 knots). Questionable/uncertain kinematic forecasts preclude higher risk probabilities at this time, but the overall synoptic regime and parameter space should still be supportive of a severe hail/wind, and potentially brief tornado, threat. ...Moore.. 05/31/2025 $$ = = = 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) .