Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Mar 02 2023 20:53:17 AWUS01 KWNH 022053 FFGMPD ARZ000-TXZ000-OKZ000-030252- Mesoscale Precipitation Discussion 0083 NWS Weather Prediction Center College Park MD 352 PM EST Thu Mar 02 2023 Areas affected...northern Texas, southern/southeastern Oklahoma, and western Arkansas Concerning...Heavy rainfall...Flash flooding likely Valid 022052Z - 030252Z Summary...Deepening convection across a broad part of north Texas and the Red River Valley area should result in scattered to numerous flash flood instances. Locally significant impacts are possible. Discussion...Recent radar mosaic indicated convection rapidly deepening across several areas: 1) along a warm front just northwest of the Dallas/Fort Worth metro area, 2) along the Red River Valley vicinity near Wichita Falls, and along a sharpening dryline just west of Dyess Air Force Base and San Angelo. These storms were responding to 1) approaching lift associated with an approaching mid-level wave over southern New Mexico, 2) steep mid-level lapse rates (on the order of 7.5-9C/km per regional 18Z soundings), and 3) strengthening low-level flow, which was maintaining a very moist/buoyant warm sector airmass south of a warm front near the Red River. Spotty areas of 1 inch/hr rainfall rates were noted with the stronger activity, and localized training of cells was also already noted with activity near Wichita Falls despite storms in that area being elevated. A few additional areas of weaker, yet deep convection were noted southeast of Dallas/Fort Worth within the past half hour as well, with sub 0.5 inch/hr rates observed there as well.=20 Expanding convective coverage is expected from 21-04Z.=20 Models/CAMs indicate that a mix of lines and convective cells should evolve especially along the warm frontal zone near the Red River. The orientation of initiation should allow for training of cells, with areas of 3-5 inch rainfall amounts expected (locally higher) especially where training/repeating of cells is most pronounced. The highest risk of experiencing these heavier rainfall totals will exist generally from just north of the Dallas/Fort Worth area northeastward to McAllister, OK eastward toward Mena, Arkansas. The eastern extent of this heavier rainfall risk will depend on a number of factors, including 1) upscale growth of any convective cluster along the Red River near Ardmore/Wichita Falls, and 2) the extent of convective coverage across a weakly capped warm sector between Dallas and Shreveport. Over time, it is also likely that individual cells can anchor along the warm front near the Red River and prolong rainfall rates within that general area, further promoting the flash flood risk.=20 Eventually, cells/clusters are expected to accelerate eastward partially in tandem with an approaching dry line over west Texas.=20 Storms could reach far western/southwestern Arkansas as early as 23Z - especially if cells mature more quickly than expected across northeast Texas and vicinity. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_NOcaR_EsKyELJq_8xyzMDiJTf6wr6jdhwdGFzWFZlpELEN_4hfxTiRH9jQ2ifjycGNr= yi-mccQ6fZA1gTSpzV8F5vQ$ for graphic product... ATTN...WFO...FWD...LZK...OUN...SHV...SJT...TSA... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 35429576 34999443 34479359 33799357 33069420=20 32209515 32169629 32829767 32889825 33079923=20 34359897 35169763=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) .