Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Sep 15 2024 07:31:16 ACUS03 KWNS 150731 SWODY3 SPC AC 150730 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sun Sep 15 2024 Valid 171200Z - 181200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE HIGH PLAINS... ....SUMMARY... Isolated severe thunderstorms will be possible across a large swath of the High Plains region, mainly from Tuesday late afternoon into the evening. Severe gusts should be the primary hazard. ....High Plains... A shortwave trough over the eastern Great Basin at 12Z Tuesday should take on a negative tilt as it advances towards the northern High Plains. This process will yield a separation of the strong upper-level jet surrounding the trough, from a meridional component shifting north into eastern WY and a zonal component holding over AZ/NM. Guidance has oscillated southward with the evolution of the meridional component relative to yesterday's guidance. Deep lee cyclogenesis is expected over northeast WY/southeast MT. This low will advance north towards the MT/SK border area by 12Z Wednesday. Large-scale ascent will be pronounced within this synoptic regime, with favorable upper-level difluence, mid-level height falls, and low-level convergence. But weak buoyancy and modest mid-level lapse rates will characterized much of the environment. The bulk of convective development will occur over the higher terrain, likely aided by the subtropical moisture plume over the Southwest. High-based storms should progress into a well-mixed boundary layer that may initially be devoid of appreciable CAPE. This lack of greater buoyancy during the late afternoon to early evening, outside of northeast MT into the Dakotas, yields substantial uncertainty in the degree of strong versus severe storms. But with scattered to widespread convection likely into the evening, sporadic severe gusts may occur. ....Eastern NC and southeast VA... The poor predictability of offshore cyclogenesis amplitude and inland progression on Monday renders minimal confidence in delineating a severe area on Tuesday. Slower and more aggressive ensemble members suggest an adequate SRH/buoyancy combination for low-topped tornado potential may linger over eastern NC early in the period and shift into parts of southeast VA. But overall trends indicate a generalized weakening low-level wind field may occur during the day. ...Grams.. 09/15/2024 $$ = = = 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) .