Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Apr 10 2024 09:29:26 AWUS01 KWNH 100929 FFGMPD MSZ000-LAZ000-TXZ000-101430- Mesoscale Precipitation Discussion 0144 NWS Weather Prediction Center College Park MD 528 AM EDT Wed Apr 10 2024 Areas affected...southeastern TX into central/southern LA and southwestern MS Concerning...Heavy rainfall...Flash flooding likely Valid 100927Z - 101430Z Summary...Heavy rain is expected to expand eastward into portions of south-central LA with scattered to numerous areas of flash flooding through 14Z, some of which could be considerable to severe with life-threatening impacts. Discussion...A persistent area of training from the southern Piney Woods region of TX into western LA has resulted in an areas of 5 to 10+ inches of rain over the past 12 hours, extending from Hardin and Tyler counties into western Vernon and Beauregard parishes. Radar imagery at 09Z showed the west to east axis of training, occurring just north of a combined outflow/stationary front, has begun to lift north over the past hour, ahead of an approaching, forward propagating convective line moving east from a Conroe to Houston to Freeport line. The VAD wind profile from KHGX at 09Z indicated southerly winds of 30-40 kt in the 2-5 kft AGL layer, ahead of the convective line, a 10 kt increase since two hours earlier. The strengthening low level flow, just ahead of a surface low and southward extending cold front near Houston, has likely helped to shift the axis of ongoing training to the north over the past hour. As a potent mid-level trough over western TX continues to advance east this morning, increased large scale ascent (including strengthening divergence and diffluence aloft) will shift eastward from eastern TX into western LA. An ongoing axis of elevated convergence in the 925-850 mb layer, crossing the Sabine River from SW to NE, is likely to be disrupted as the upper trough and preceding convective line advance eastward this morning. Overrunning low level flow of 30-40 kt will translate eastward into LA over the next few hours, tapping a notable region of 1000 to 2000+ J/kg MLCAPE located off of the upper TX and LA coast, supporting continued heavy rainfall. Mean steering flow will be oriented from SW to NE, but west to east mean translation of the heavy rainfall axis is expected which should result in continued training, with rainfall rates of 1-2 in/hr, locally 2 to near 3 in/hr. Additional rainfall totals of 3-5 inches (locally higher) are expected through 14Z, which is likely to extend a significant flash flood threat eastward from southeastern TX into portions of central/southern LA. Any overlap of heavy rain which has fallen over the past 12 hours will maintain a risk of considerable or major flash flooding with the Sabine River Valley, and possibly eastward into portions of central or south-central LA. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6ZE7u-y-0Atg76IMZo6JIp8eZE5Csowe5WQR4igBhMfpqN6rZ2b9kcsSLWpCIj-f4nas= UXVi-hJ5E-9Judjl7zS-HEg$ for graphic product... ATTN...WFO...HGX...JAN...LCH...LIX...SHV... ATTN...RFC...LMRFC...WGRFC...NWC... LAT...LON 31849202 31649106 31229053 30558992 30158962=20 29798980 29609040 29729173 29739326 29509480=20 29789521 30389498 31029423 31419344=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .