Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Apr 02 2023 17:29:46 ACUS02 KWNS 021729 SWODY2 SPC AC 021728 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Sun Apr 02 2023 Valid 031200Z - 041200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL GULF COAST STATES...SOUTHERN PLAINS...AND MID MISSISSIPPI VALLEY/MIDWEST... ....SUMMARY... Isolated to widely scattered severe thunderstorms appear possible across parts of the central Gulf Coast states, mainly through early Monday evening. More isolated strong to severe thunderstorms may occur across portions of the southern Plains, and mid Mississippi Valley/Midwest vicinity, late Monday afternoon through Monday night. ....Synopsis... A pronounced western CONUS upper trough is forecast to amplify further on Monday as it digs over the Great Basin and Southwest. Strong surface lee cyclogenesis will occur in earnest over the central High Plains as large-scale ascent overspreads this region through the period. Low-level moisture emanating from the open Gulf of Mexico will stream northward Monday across parts of the southern/central Plains, lower/mid MS Valley, Southeast, and Midwest. A surface dryline will mix eastward through Monday afternoon over portions of central/eastern OK/TX. ....Lower Mississippi Valley/Mid-South into the Southeast... A low-amplitude shortwave trough should move quickly eastward across the Southeast and towards the East Coast Monday morning. Ascent associated with this feature and related low-level warm advection will likely aid thunderstorms that should be ongoing Monday morning over parts of MS into AL. At least weak destabilization should occur through Monday afternoon over parts of southern AL/GA and the FL Panhandle as daytime heating occurs and surface dewpoints increase into the mid to upper 60s along/south of a front. A mix of multicells and perhaps occasional supercell structures may persist and spread slowly east-southeastward across this area, as deep-layer shear should remain strong enough to support continued updraft organization. Isolated damaging winds and large hail should be the main threats with this activity, but sufficient low-level shear should be present along/near the front for some updraft rotation and perhaps a tornado or two. ....Southern Plains... Well ahead of the western CONUS upper trough, mid-level heights are forecast to remain neutral on Monday, or even rise slightly through the day. The surface dryline is expected to mix eastward across parts of central/eastern OK/TX by late Monday afternoon. Nebulous/weak large-scale ascent and a persistent low-level inversion associated with an EML/steepening mid-level lapse rates should inhibit convective development for much of the day. Latest (12Z) guidance shows generally little signal for thunderstorms to initiate along the dryline Monday afternoon/early evening. But, there still appears to be a conditional threat for a supercell to develop by peak afternoon heating. If a thunderstorm can form, it would exist in rather favorable thermodynamic and kinematic environment to support both large hail and damaging winds. Have adjusted the Marginal Risk based on the consensus of the forecast position of the dryline, but confidence in convection occurring remains too low to include higher severe hail/wind probabilities. ....Central Plains into the Mid Mississippi Valley and Midwest... Modest low-level moisture should return slowly northward across this region as a warm front gradually sharpens by Monday evening. Most guidance suggests that a cap will limit robust thunderstorm development through much of the day. But, increasing ascent attendant to a strengthening west-southwesterly low-level jet may aid convective initiation along/north of the front Monday evening and overnight. If thunderstorms can form, they would likely remain elevated and pose a threat for mainly isolated hail as they move eastward from parts of the mid MS Valley to the Midwest. ...Gleason.. 04/02/2023 $$ = = = 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) .