Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Aug 18 2024 05:33:18 ACUS01 KWNS 180533 SWODY1 SPC AC 180532 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Sun Aug 18 2024 Valid 181200Z - 191200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDDLE ATLANTIC TO THE DEEP SOUTH... ....SUMMARY... Scattered wind damage will be possible from the Mid-Atlantic States to the Deep South from mid-afternoon to early evening on Sunday. ....Middle Atlantic to Deep South... Great Lakes/OH Valley upper trough will shift east today with a 19/00z position forecast along the spine of the Appalachians. Modest 500mb flow should extend within the base of the trough into the Middle Atlantic. This flow regime will aid the organizational potential of convection that evolves ahead of the primary synoptic front. Latest model guidance suggests a weak surface low may develop over northern VA/MD by late afternoon and this feature should track into NJ during the overnight hours. While deep-layer flow is not forecast to be exceptionally strong, 0-6km bulk shear will exceed 30kt within a warm-advection zone. Forecast soundings favor storm rotation and a few supercells may ultimately evolve across this region. In addition to damaging wind threat, some risk for hail and perhaps a brief tornado can be expected. Trailing front across the Deep South will not be particularly convergent as it surges into GA-AL-MS. Pre-frontal boundary layer will be adequately buoyant for robust updrafts and any storms that evolve ahead of the wind shift will do so within an environment that favors some organization. Convection will propagate southeast toward the Gulf Coast as northwesterly flow deepens with trough passage. ....Rockies/Central Plains... Water-vapor imagery depicts a well-defined short-wave trough topping the Rockies ridge over western WY at this time. This feature will track southeast across the central Plains this afternoon as a 500mb speed max translates into the lower MO Valley. LLJ will respond to this feature which should contribute to an extensive zone of elevated convection early in the period. This activity will propagate southeast along a sharp corridor of warm advection into eastern KS, then into the lower MS Valley during the overnight hours. Have increased severe probabilities to account for this evolution. Primary concern is damaging winds. ....Interior West... Isolated strong/locally severe thunderstorms will once again develop across western UT and track north-northeast along the western/northern periphery of the dominant anticyclone. Gusty winds are possible with this diurnally enhanced activity. ...Darrow/Squitieri.. 08/18/2024 $$ = = = 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) .