Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Mar 01 2023 16:32:15 ACUS01 KWNS 011632 SWODY1 SPC AC 011630 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Mar 01 2023 Valid 011630Z - 021200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE ARKLATEX INTO THE MID-SOUTH... ....SUMMARY... A focused corridor of severe potential is evident this afternoon through tonight from northeast Texas into the Mid-South and Tennessee Valley. Scattered large to very large hail, damaging winds, and tornadoes all appear possible. A strong tornado may also occur. ....Southern Plains into the Mid-South and Tennessee Valley... A broad area of enhanced southwesterly mid-level flow will persist today through tonight across the southern Plains into the MS Valley and OH Valley. At the surface, a front extends from north TX into MO and the Midwest. Low-level moisture is forecast to gradually increase this afternoon and evening along/south of this boundary. A strong cap noted on the 12Z SHV sounding should inhibit robust convective development for at least a few more hours. Eventually, subtle large-scale forcing associated with a low-amplitude mid-level perturbation over TX, along with modest low-level convergence along the front, should support convective initiation over northeast TX/the ArkLaTex region by late this afternoon. Steep mid-level lapse rates, increasing low-level moisture, and filtered daytime heating should support moderate instability in a narrow corridor from northeast TX into the Mid-South. Deep-layer shear in excess of 50 kt will easily support organized thunderstorms, including supercells. Scattered large to very large hail will be threat with any initially discrete convection that develops. With time, thunderstorms should congeal into one or more bowing line segments as they spread eastward across the Mid-South and TN Valley this evening and tonight. The damaging wind threat should increase across these areas as this mode transition occurs. While there is still some uncertainty, most guidance also suggests that a southerly low-level jet will modestly strengthen this evening to around 30-35 kt. A narrow zone of more favorable tornado potential may exist across parts of southern/central AR into northern MS and southwestern TN, particularly if supercells can remain at least semi-discrete. A strong tornado appears possible in this corridor. Based on consensus of 12Z guidance, confidence has increased in a more concentrated corridor of severe potential across this region, warranting the addition of an Enhanced Risk. ....Ohio Valley... The cold front should advance quickly east-southeastward across the OH Valley through this evening. Low-level moisture will remain more limited compared to locations farther south. Still, steep lapse rates and ample daytime heating ahead of the front should aid in the development of weak instability this afternoon. Isolated strong to severe thunderstorms capable of producing both hail and damaging winds appear possible. ...Gleason/Thornton.. 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) .