Subj : MESO: Mesoscale Discussion 0241 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Mar 03 2023 06:27:00 ACUS11 KWNS 030626 SWOMCD SPC MCD 030626=20 MSZ000-ARZ000-LAZ000-030830- Mesoscale Discussion 0241 NWS Storm Prediction Center Norman OK 1226 AM CST Fri Mar 03 2023 Areas affected...portions of southeastern AR...western MS...and northeastern LA Concerning...Tornado Watch 59... Valid 030626Z - 030830Z The severe weather threat for Tornado Watch 59 continues. SUMMARY...A line of severe thunderstorms is currently moving northeastward across southern AR and the vicinity. As boundary-layer conditions improve beneath a strengthening low-level jet, this line of storms may pose an elevated threat for damaging wind gusts and a few tornadoes during the next couple of hours. DISCUSSION...A well-established QLCS, forced by a surface cold front and increasingly divergent flow aloft, continues to propagate northeastward across WW 59 to the south of a stationary front draped through central AR. In the last couple of hours, the portion of the line extending from roughly KSUZ-KELD has been responsible for strong wind gusts as well as a couple of stronger low-level mesovortices. Some of these have been associated with embedded supercell-like structures, such as the ongoing, previously tornado-warned mesovortex located in Hot Spring/Saline counties in AR. These storms have persisted in the last couple of hours despite 00z HREF guidance suggesting that they would gradually weaken by this time. Current thinking is that the observed trend is due to slightly cooler temperatures aloft (around 700 mb) than advertised in forecast CAM soundings. For example, while observed PERiLS soundings reveal slight warming at 700 mb (up to around 3-4 degrees C by 05z), latest HRRR runs showed 700-mb temperatures upwards of 7-8 C. Latest 05z RAP thermodynamic and kinematic profiles closely matched the PERiLS observations and -- given advertised evolution of the RAP profile in the next couple of hours -- suggest that the localized threat for damaging winds and embedded QLCS tornadoes may increase in this corridor. This threat is conditional on continued short-term boundary-layer warming and moistening, which at least partially appears to be underway given recent Sticknet surface observations. ...Flournoy.. 03/03/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!69lhU8NQgrd88js_sdzmHRVi4gmOhLmecxJYUgztFCsidgM06uBWMyeIVPasEZ9ZFx4oJfKRd= fnn77kKJSsmG9m9CHc$ for graphic product... ATTN...WFO...MEG...JAN...LZK...SHV... LAT...LON 34279237 34679198 34719109 34309025 33519004 32859060 32629173 32609256 33089289 33879271 34279237=20 =3D =3D =3D 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) .