Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Mar 21 2023 17:12:33 ACUS02 KWNS 211712 SWODY2 SPC AC 211711 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1211 PM CDT Tue Mar 21 2023 Valid 221200Z - 231200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST KANSAS INTO NORTHEAST ILLINOIS AND NORTHWEST INDIANA... ....SUMMARY... Isolated strong to severe thunderstorms capable of large hail are possible from far northeast Kansas across northern Missouri and into the lower Lake Michigan region late Wednesday evening into early Thursday morning. ....Synopsis... An upper wave approaching the southern CA coast is forecast to deepen over the next 24-48 hours across the southwestern CONUS. As this occurs, strengthening zonal flow over the central Rockies will foster the development of a weak lee cyclone over the central Plains by Wednesday afternoon. This low will aid in northward advection of upper 50s/low 60s dewpoints into the lower Missouri River Valley as it moves to the northeast along a diffuse stationary frontal zone left in the wake of a leading shortwave trough across the upper MS Valley/Lake Superior region. The combination of gradually improving low-level moisture and steepening mid-level lapse rates will bolster buoyancy along the frontal zone with MUCAPE as high as 1000-1500 J/kg by late evening across northern MO into central IL. Strengthening flow aloft ahead of the deepening synoptic wave to the west will elongate hodographs and support effective bulk shear values in excess of 40 knots during the overnight hours. Convective initiation appears most likely during the 00-03 UTC period across northern MO/western IL within a warm advection regime ahead of the migratory surface low. Initially discrete storms are expected to gradually grow upscale into clusters given mean flow and deep-layer shear vectors generally oriented along the frontal zone. However, the thermodynamic/kinematic environment should support some degree of storm organization, including the potential for a few elevated supercells capable of large hail and perhaps a strong gust or two. Confidence in the severe threat decreases with eastern extent into IN/lower MI where weaker mid-level lapse rates are expected, but a mature storm or two may migrate into this region during the early morning hours Thursday given the favorable kinematic environment. ...Moore/Smith.. 03/21/2023 $$ = = = 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) .