Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Mar 22 2023 06:01:21 ACUS02 KWNS 220601 SWODY2 SPC AC 220559 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Wed Mar 22 2023 Valid 231200Z - 241200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL/EASTERN OKLAHOMA INTO THE TEXAS HILL COUNTRY... ....SUMMARY... Thunderstorms capable of hail, some very large, and damaging gusts are possible Thursday afternoon through Friday morning across the southern Plains. ....Synopsis... Presence of western CONUS troughing and subtropical ridging over the Gulf of Mexico will contribute to a belt of enhanced southwesterly flow extending from northern Mexico northeastward across the central Plains and Mid MS Valley early Thursday. A pair of shortwave troughs will be embedded within this belt of stronger flow, one initially near the Mid MO Valley and the other across southern AZ/northern Mexico. Both shortwaves are expected to progress northeastward, with the second shortwave moving through the southern High Plains during the afternoon/evening, reaching KS/OK by early Friday morning. The surface pattern Thursday morning will likely feature a low near the northern IL/IN border vicinity, with a cold front extending southwestward to another low over northwest TX. This front is expected to move eastward/southeastward across the OH Valley, while the southern portion moves more southeastward/southward across the Ozark Plateau and much of OK. Guidance varies on the position of the front over OK. Secondary surface cyclogenesis is anticipated over the TX Low Rolling Plains Thursday afternoon, with the resulting low then moving eastward into north TX. ....OH Valley Thursday morning... Elevated thunderstorms will likely be ongoing near the surface low across northern IL/northern IN early Thursday morning. Strong vertical shear and steep mid-level lapse rates will be in place, supporting the potential for a few strong updrafts capable of hail. These early morning storms are expected to continue eastward, likely outrunning most of the buoyancy as they move into OH during the late morning. ....Southern Plains Thursday afternoon through Friday morning... Low 60s dewpoints are expected be in place along the front early Thursday morning, likely increasing into the mid 60s by the late afternoon. Recent guidance has trended slower with the front, keeping more of central and eastern OK ahead of the front during the afternoon. Increasing low-level moisture coupled with modest daytime heating should destabilize the airmass south of the front by the late afternoon. This instability coupled with convergence along the front is expected to result in thunderstorm development, likely beginning over central OK. Vertical shear will be strong, and the initial more cellular development may produce large hail. Front-parallel deep shear should result in any near-front development tracking northward over the front quickly, likely limiting the surface-based warm sector development. Even so, a brief temporal window for may exist for damaging gusts and/or a tornado. Thunderstorm development is also anticipated farther south, ahead of the deepening surface low expected to move into northwest TX during the early evening. A more cross-boundary vertical shear vector is anticipated here, which could support a greater potential for storms to stay surface-based. However, the presence of low-level stability suggest an elevated storm mode, with the cold front acting as the initiation mechanism. Like the storms farther north, hail is the main severe threat, with some very large hail possible. As the low and associated front continue eastward, storm coverage should increase southward across the TX Hill Country/Edwards Plateau. Hail and damaging gusts are possible with this line of storms as it moves eastward toward central TX early Friday morning. ...Mosier.. 03/22/2023 $$ = = = 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) .