Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Sep 09 2023 06:00:51 ACUS02 KWNS 090600 SWODY2 SPC AC 090559 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sat Sep 09 2023 Valid 101200Z - 111200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS NORTHWEST TEXAS INTO THE CENTRAL HIGH PLAINS AND SOUTHERN WYOMING... ....SUMMARY... Isolated severe thunderstorms are possible from parts of the southern High Plains northward into the central High Plains and southern Wyoming on Sunday and Sunday evening. ....Synopsis... Model guidance on Sunday depicts a weak mid-level trough over the Appalachians and another weak trough over western Ontario and the Upper Midwest. A mid-level anticyclone will reside over northwestern Mexico and a mid-level ridge over the northern Rockies. A belt of enhanced westerly mid-level flow is forecast over the central Rockies eastward into KS. In the low levels, a surface front will extend from the Upper Midwest into the central High Plains. ....Central High Plains vicinity into the southern High Plains... Showers/thunderstorms may be ongoing Sunday morning near and north of the surface boundary near the CO/NE/KS border. Models continue to show a weak mid-level disturbance moving east from the central Rockies into the High Plains during the day. It is uncertain whether this activity will continue into the midday hours as it moves southeast. Additional storms are forecast to develop near the higher terrain in lee of the Sangre de Cristos. A cluster or two may eventually evolve across eastern CO and from northeast NM into the TX Panhandle/Caprock. Large veering of flow with height will aid in storm organization, especially where low-level lapse rates steepen within a moist plume over the region. Some of the stronger storms may result in an isolated large hail/severe gust threat mainly during the afternoon into the evening. Farther north over southern WY, heating will steepen lapse rates and potentially favor localized severe gusts with the stronger downdrafts. This activity will peak during the late afternoon and likely subside by the early evening. ....Mid-Atlantic states into the Northeast... Model guidance continues to show scattered diurnal thunderstorms developing from VA northward into southern New England. The greatest instability will likely be over the Mid-Atlantic states where warmer temperatures will result in 1000 J/kg MLCAPE (500 J/kg or less in southern New England/NY). Weak mid-level lapse rates and moist profiles will limit overall updraft vigor with the stronger storms that develop. Given only modest low to mid-level flow forecast, storm organization potential will likely be limited. Although a few locally strong gusts cannot be ruled out, low confidence and the spatial uncertainty/magnitude of the threat continue to preclude low-severe probabilities. ...Smith.. 09/09/2023 $$ = = = 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) .