Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Oct 13 2024 05:48:37 ACUS01 KWNS 130548 SWODY1 SPC AC 130546 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1246 AM CDT Sun Oct 13 2024 Valid 131200Z - 141200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL/EASTERN WV TO MIDDLE/EASTERN TN... ....SUMMARY... Strong to locally severe thunderstorms are possible, mainly this evening, across parts of the central/southern Appalachians and Tennessee Valley. Isolated wind damage and marginally severe hail are the expected hazards. ....Central/southern Appalachians and the TN Valley... A vigorous shortwave impulse will dig through the basal portion of a mid/upper trough and yield amplification of this trough southward across the Great Lakes through Monday morning. Appreciable mid-level height falls will overspread the central/southern Appalachians into the TN Valley, mainly during the evening and overnight. A leading and weaker mid-level impulse should yield the primary surface cyclone moving east across PA during the afternoon to early evening. A surface cold front will extend southwest of this low into the TN Valley. Convective development along the front appears likely to be delayed until early evening, as the strengthening large-scale ascent aids in increasing low-level convergence along the boundary amid pervasive veered flow within the warm sector. Surface dew points should largely range from the mid 50s in WV to a narrow corridor of low 60s in Middle TN, yielding a plume of modest buoyancy between 500-1500 J/kg amid initially steep mid-level lapse rates. Guidance differs greatly in the degree of storm coverage, from nil to scattered, perhaps in response to the ascent strengthening after peak diurnal heating. The strongest 700-mb westerlies, in excess of 50 kts, should be confined northeast of TN. Forecast hodographs above this level appear small, owing to weakening winds with height as fast mid/upper flow lags to the north-northwest. This suggests supercell structures may struggle to develop/be sustained. But the strong 700-mb flow could support localized damaging winds in any multicell clusters. Farther southwest, somewhat greater buoyancy could foster small to marginally severe hail as well. The overall severe threat appears likely to remain marginal and isolated. ...Grams/Halbert.. 10/13/2024 $$ = = = 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) .