Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Sep 07 2023 17:47:14 ACUS02 KWNS 071747 SWODY2 SPC AC 071745 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1245 PM CDT Thu Sep 07 2023 Valid 081200Z - 091200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN PORTIONS OF THE SOUTHERN PLAINS AND ACROSS THE SABINE RIVER VALLEY...AND OVER PARTS OF THE NORTHEAST AND MID-ATLANTIC REGION... ....SUMMARY... Thunderstorms, associated with a marginal severe threat, will be possible on Friday across parts of the Northeast, Central Appalachians, Mid-Atlantic, Ark-La-Tex and Northern High Plains. ....Southeastern Oklahoma/eastern Texas/southwestern Arkansas/western Louisiana... Thunderstorms are forecast to be ongoing at the start of the period across parts of the eastern Oklahoma/western Arkansas region, possibly accompanied by some ongoing potential for strong winds/hail. A strong model signal remains apparent that storms will shift southward with time, strengthening gradually as daytime heating results in a corridor of moderate instability. Given a belt of 35 to 45 kt mid-level north-northwesterly flow around the eastern fringe of the southwestern U.S. upper ridge, potential for an organized MCS moving quickly southward roughly along the Sabine River Valley through the day may evolve. In this scenario, potential for damaging winds would be expected, along with some hail, with the risk shifting southward and likely reaching the Gulf Coast by late afternoon. While less certain, some hints exist within some models that late evening/overnight redevelopment of storms could occur on the western flank/remnant outflow from this initial band of storms, across the north-central Texas vicinity, with potential for a second/southeastward-moving MCS. These storms -- should they develop/organize, could also pose risk for hail and damaging winds through the overnight period. ....The Northeast and Mid-Atlantic region... Afternoon heating/destabilization is expected along and east of the Appalachians Friday, near a weak/stalled surface front. Terrain-induced ascent, and lift near the front, will result in scattered thunderstorm development during the afternoon, particularly from the mountains of Virginia and West Virginia northeastward into New England. With a belt of 25 to 35 kt south-southwesterly flow across this area, on the eastern fringe of the mid-level trough positioned over the Midwest/Tennessee Valley, shear will support a few organized storms/storm clusters. As these clusters shift northeastward, locally damaging wind gusts can be expected, lingering into the early evening hours before storms begin to nocturnally weaken. ....Northern Intermountain region... Daytime heating across the northern Intermountain region will result in modest destabilization, with mixed-layer CAPE averaging 500 J/kg during the afternoon atop a deep mixed layer. As a short-wave trough at mid levels sweeps eastward across the region, isolated to widely scattered thunderstorm development is expected, with peak convective coverage anticipated from late afternoon through mid evening. With a belt of 30 to 40 kt mid-level westerlies accompanying the short-wave trough, and potential for sub-cloud evaporative effects, a few stronger/longer-lived storms may produce gusty/locally damaging winds. ...Goss.. 09/07/2023 $$ = = = 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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .