Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Apr 27 2025 19:29:58 ACUS03 KWNS 271929 SWODY3 SPC AC 271929 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 PM CDT Sun Apr 27 2025 Valid 291200Z - 301200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN PARTS OF OH TO WESTERN PA/NY... ....SUMMARY... Scattered severe thunderstorms are likely across parts of the Lower Great Lakes on Tuesday afternoon/evening. Scattered severe thunderstorms are possible southwestward into the southern Great Plains. Isolated significant-severe potential, mainly from hail, is apparent across west Texas and separately in parts of the eastern Midwest to Lower Great Lakes. ....Synopsis... A consolidated shortwave trough should move east across the Great Lakes and southeast Canada. A southern-stream trough over the Southwest to northwest Mexico should drift east. Primary surface cyclone over northeast ON should quickly progress towards the Canadian Maritimes. An attendant cold front will push across the central to Lower Great Lakes Tuesday afternoon and evening. A weaker surface low should remain anchored over the TX Trans-Pecos. ....Eastern Midwest/Lower Great Lakes... The eastern extent of a pervasive EML will support potential for at least moderate buoyancy across a broadening warm-moist sector ahead of the aforementioned cold front. Rather strong mid-level westerlies should be present from the Great Lakes vicinity northward, trailing in magnitude but still moderate to strong across the OH Valley. While evolution of early-day convection from late D2 is uncertain, potential exists for pronounced boundary-layer heating amid robust low-level moistening to the northeast. With stronger mid-level height falls north of the international border, overall setup could favor discrete to semi-discrete supercells that eventually merge into clusters/short lines by evening. Confidence is sufficient in upgrading/expanding categorical risks along with adding a significant severe highlight, most likely for hail at this time. ....TX/OK... Multiple rounds of thunderstorms are expected through the period along a convectively modulated, quasi-stationary baroclinic zone. This renders enough uncertainty to mitigate a corridor of greater severe potential, but a mesoscale-driven Enhanced Risk may be needed in later outlooks. Adequate mid-level southwesterlies will persist through the period for supercells, with most guidance hinting at training convection along the west/southwest to east-northeast oriented portion of the zone near the Red River. More probable scenario for very large hail should exist to the southwest of that corridor, with a few dryline supercells favored in the late afternoon to early evening. ...Grams.. 04/27/2025 $$ = = = 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) .