Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Mar 22 2023 07:35:49 ACUS03 KWNS 220735 SWODY3 SPC AC 220734 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0234 AM CDT Wed Mar 22 2023 Valid 241200Z - 251200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN LOUISIANA...SOUTHWEST ARKANSAS...AND WESTERN MISSISSIPPI... ....SUMMARY... Supercell thunderstorms capable of all severe hazards, including strong tornadoes, are possible across the Lower Mississippi Valley on Friday. ....Synopsis... The upper pattern early Friday morning will likely be characterized by broad troughing across the western CONUS and subtropical ridging centered over the Straits of Florida. Enhanced mid-level flow will extend throughout western and southern periphery of the upper trough and then throughout the northwestern periphery of the subtropical ridge. A low-amplitude shortwave trough is forecast to move from the base of the upper trough quickly eastward across the southern Plains throughout the day, and then more northeastward across the Mid-South overnight. Strong mid-level flow (i.e. 100 kt at 500-mb) will accompany this shortwave, spreading across TX into the Mid-South. The surface pattern preceding this shortwave trough is expected to feature a low over north TX early Friday, with a cold front extending southward from this low into the TX Hill Country and a stationary front extending northeastward into the Middle OH Valley. This low is forecast to move northeastward throughout the day, while deepening significantly. ....Lower MS Valley... Expectation is for a broad area of upper 60s dewpoints to be in place from east TX across the Lower MS Valley, ahead of the surface low and associated front. Cloud cover may temper daytime heating, but afternoon temperatures will likely still reach the 80s, contributing to moderate buoyancy across much of the region. In addition to this buoyancy, moderate mid-level flow atop strengthening low-level flow (supported by the maturing cyclone ahead of the approaching shortwave trough) will contribute to long hodographs with substantial low-level magnitude and veering. As a result, the environment will be very favorable for supercells. Current expectation is for storms to develop during the afternoon over southwest AR and western LA (perhaps as far west as east TX). This development should occur ahead of the cold front within the open warm sector, maturing as it moves eastward across the Lower MS Valley. A discrete supercell mode is anticipated initially, with all severe hazards possible, including strong tornadoes. Upscale growth into a convective line is anticipated after this initially discrete mode, with the line pushing eastward across MS and AL overnight. ....Mid MS Valley... Despite less buoyancy that areas farther south, augmented forcing for ascent close to the surface low could result in bowing line segments capable of damaging wind gusts and embedded tornadoes Friday afternoon through Friday evening. ...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) .