Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Sep 09 2024 05:52:11 ACUS01 KWNS 090552 SWODY1 SPC AC 090550 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 09 2024 Valid 091200Z - 101200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN GREAT LAKES VICINITY... ....SUMMARY... Thunderstorms will be possible today over parts of the eastern Great Lakes, along the Gulf Coast, and from the Four Corners northward into the northern Plains. Isolated storms may produce damaging wind gusts over western and central New York State. ....Synopsis... A large upper ridge will remain in place over the Central CONUS flanked by broad trouging to the west and a lingering upper low over eastern Canada. Behind the upper low, a secondary embedded shortwave trough and speed max are forecast to move south out of western Ontario and over the Great Lakes, providing adequate lift for scattered thunderstorms over parts of the Northeast. To the west, scattered thunderstorms are likely over the Great Basin into the Four Corners, with a few thunderstorms possible over the Northern Plains ahead of the western US trough. Finally, scattered thunderstorms may also develop by afternoon peak heating along the Gulf Coast into FL and near the outer bands of PTC6. ....Great Lakes vicinity... As the aforementioned mid-level speed max approaches from southern Canada, shower and thunderstorm activity should begin to increase in coverage and intensity in the vicinity of Lakes Erie/Ontario, as well as over portions of northwestern NY State by mid morning. Limited, but adequate, surface moisture (dewpoints in the mid 50s to near 60 F), combined with daytime heating, and 500 mb temps of -18 to -20C will support weak destabilization (MLCAPE 500-700 J/kg) across parts of the lower Great Lakes and Northeast. Low-topped bands or clusters of predominately multicell storms are likely, and may briefly organize owing to increasing flow aloft aiding deep-layer shear to near 30 kt. Despite the weak buoyancy, fairly steep low-level lapse rates (~7 C/km) beneath the upper low, may support a few damaging gusts and instances of small hail with the strongest storms through the afternoon. Convection should eventually outrun the more robust buoyancy and weaken to the southeast into parts of northern PA and southern New England this evening. ...Lyons.. 09/09/2024 $$ = = = 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) .