Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Mar 01 2023 17:38:47 ACUS02 KWNS 011738 SWODY2 SPC AC 011736 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1136 AM CST Wed Mar 01 2023 Valid 021200Z - 031200Z ....THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST TX INTO SOUTHWEST AR AND NORTHWEST LA... ....SUMMARY... A regional severe-thunderstorm outbreak appears likely across parts of the southern Plains into the ArkLaTex and ArkLaMiss regions Thursday into Thursday night, with a few strong tornadoes, widespread damaging wind, and hail all expected. ....Synopsis... Upper low currently moving through central CA is forecast to continue southeastward today before then pivoting eastward tonight and reaching the AZ/NM border by early Thursday morning. Continued eastward progression across the southern High Plains is anticipated during the day Thursday. A trend towards a negative tilt and a bit more northeastward motion is expected Thursday night into Friday morning as the low moves across the southern Plains. Strong mid-level flow will accompany this system, with 100+ kt flow at 500 mb spreading eastward across TX Thursday afternoon and through the Arklatex by early Friday morning. Surface pattern will likely feature a weak frontal low over the TX Big Country early Thursday morning, with a warm front extending from this low northeastward through southeast OK and southern AR. Expectation is for this low to progress northeastward along the warm front into southeast OK by the afternoon, while a more substantial low develops farther west with the main ascent associated with the upper low. This primary low is then expected to move quickly eastward Thursday evening and overnight, as an attendant cold front sweeps across TX and the Lower MS Valley. ....Central/East TX into Lower MS Valley... Ample low-level moisture with surface dewpoints in the mid to upper 60s will be in place across the region ahead of the approaching upper low. Strengthening low to mid-level flow within this moist and buoyant environment will set the stage for numerous severe thunderstorms as the upper low moves through Thursday afternoon into Friday morning. Thunderstorms will likely be ongoing in the vicinity of the warm front from southwest TX through the Mid-South. A few stronger storms are possible within this corridor during the morning, but the primary severe threat is expected to begin over the warm sector Thursday afternoon. Wind profiles throughout the warm sector will support supercells, but warm mid-level temperatures and weak ascent introduce uncertainty regarding the location and coverage of any warm sector storms. Mesoscale ascent associated with the weak wave low mentioned in the synopsis may provide enough ascent to initiate a few discrete cells across northeast TX, which could then move downstream into southeast OK, southwest AR, and northwest LA. Persistent warm-air advection could also moisten the low to mid-levels just enough to initiate a few storms. Given the wind profiles, storms that mature should become supercells capable of all severe hazards, including very large hail, strong wind gusts, and tornadoes. A strong tornado is possible. A more widespread severe thunderstorm risk is expected to develop across southwest TX/TX Big Country during the late afternoon as the front moves through. Strong ascent along the front coupled attendant to the upper low should result in a line of severe storms. This line is forecast to move quickly eastward throughout the evening. Robust kinematic fields associated with strong mid-level flow and a strengthening low-level jet will support both strong wind gusts and embedded QLCS tornadoes with this squall line as it moves eastward. The same corridor most favorable for the afternoon discrete storms (i.e. from northeast TX into southern AR and northwest LA) will remain the most favorable for additional severe Thursday night. ...Mosier.. 03/01/2023 $$ = = = 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) .