Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Apr 28 2025 17:26:48 ACUS02 KWNS 281726 SWODY2 SPC AC 281725 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Mon Apr 28 2025 Valid 291200Z - 301200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN OH TO WESTERN NY AND PARTS OF WEST TX TO SOUTHWEST OK... ....SUMMARY... Scattered severe thunderstorms are possible within a broad swath from the Lower Great Lakes to the southern High Plains, mainly during the afternoon to evening on Tuesday. More probable corridors of greater threat are apparent over the Upper Ohio Valley/Lower Great Lakes and in parts of west Texas into southwest Oklahoma. ....Synopsis... A consolidated shortwave trough will accelerate eastward across the Great Lakes and southeast Canada, while a southern-stream trough over the Southwest to northwest Mexico slowly moves east. Primary surface low near the northern ON/QC border will quickly progress towards the Canadian Maritimes. An attendant cold front will push across the Lower Great Lakes Tuesday afternoon and evening. A weaker surface low should remain anchored over the TX Trans-Pecos. ....OH Valley and Lower Great Lakes... Forecast scenario is marred by uncertainty regarding evolution of remnant convection on Tuesday morning in the Midwest to Lower OH Valley, and signals for weaker mid-level lapse rates/instability relative to yesterday. Consensus of guidance suggests this morning convection should persist east and strengthen early in the diurnal heating cycle into the Upper OH Valley along related large-scale outflow. This could temper the northern extent of overall severe-storm coverage/intensity, as destabilization ahead of the cold front becomes limited. A distinct outlier in guidance, the 12Z ARW-NSSL, still indicates a favorable scenario for a more widespread wind and embedded hail threat, centered on the level 3-ENH risk area. The northern extent of the severe threat appears more conditional, but a few supercells remain possible with strong deep-layer shear and greater large-scale ascent in the lee of the Lower Great Lakes. ....West TX to the Ozarks... Multiple rounds of thunderstorms are expected through the period along a quasi-stationary front that should shift slowly south via convective outflows. With persistent moderate to strong mid-level southwesterlies downstream of the AZ/NM trough, supercells and organized clusters are anticipated along the baroclinic zone. Peak severe threat should remain diurnally driven as differential heating across the composite front/outflows increases. The most probable corridor for supercells producing very large hail and a couple tornadoes appears to be from parts of the Permian Basin into southwest OK during the late afternoon. This activity should consolidate into broad clusters/MCSs by early evening with small-scale bowing structures possible. This should support isolated to scattered severe gusts as well before convection subsides. Another round of isolated severe is expected in the Permian Basin/TX South Plains vicinity Tuesday night, as the low-level jet strengthens south of the convectively modulated front. ...Grams.. 04/28/2025 $$ = = = 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) .