Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Apr 10 2024 03:58:20 AWUS01 KWNH 100358 FFGMPD MSZ000-LAZ000-TXZ000-100915- Mesoscale Precipitation Discussion 0142 NWS Weather Prediction Center College Park MD 1157 PM EDT Tue Apr 09 2024 Areas affected...southeastern TX into south-central LA and western MS Concerning...Heavy rainfall...Flash flooding likely Valid 100356Z - 100915Z Summary...Training of heavy rain is expected to impact portions of southeastern TX into south-central LA through 09Z. Localized rainfall rates near/over 3 in/hr are expected and 6-hr totals of 3 to over 6 inches will be possible. Some significant flash flooding may occur. Discussion...Regional radar and infrared satellite imagery at 0330Z showed an MCS advancing over the Lower MS Valley with upstream training of thunderstorms along its southwestern flank in southeastern TX. Observed rainfall rates within the axis of SW to NE training in southeastern TX have been observed near 3 in/hr and 2 to 4 inches have already occurred over Hardin and Tyler counties within the past 3 hours. Thunderstorms over southeastern TX into western LA were forming along a low level convergence axis in the 925-550 mb layer, with steering flow parallel to the convergence axis, supporting training. SPC mesoanalysis data from 03Z showed ample MLCAPE of 1500 to 2500+ J/kg over southeastern TX with little to no inhibition. 925-850 mb winds are forecast by the RAP to maintain a southerly fetch with 25-35 kt speeds slowly translating east into western LA over the next few hours, but with the convergence axis remaining in roughly the same place for at least the next 2-4 hours. A concern for significant rainfall totals and possibly significant flash flooding comes from expected upstream development, already underway with a forward propagating cell just west of College Station and additional development in the vicinity of San Antonio. The eastward movement of a mid/upper level trough over West Texas is expected to allow for increasing thunderstorm development within the instability pool over southeastern TX near a stationary front analyzed west to east across central/southeastern TX into LA. While the axis of ongoing training along the Sabine River may begin to shift east with time, additional upstream development is likely to support the development of training from west to east near the stationary front from portions of southeastern TX into south-central LA. Rainfall rates of 2 to near 3 in/hr will be possible at times and 6-hr totals through 09Z are expected to climb into the 3 to 6 inch range, with localized totals higher than 6 inches possible. These high rainfall totals are expected to result in scattered to numerous areas of flash flooding, some of which could be tied associated with considerable impacts. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6-4oduyQK8aPlq83GTwa1tpTTlHQCs04I7TWggqDd7ZfNL1yQ69KrgFtwmukcQkWH1G0= htUaOrLdc9agSBU8b7tB5m4$ for graphic product... ATTN...WFO...HGX...JAN...LCH...LIX...SHV... ATTN...RFC...LMRFC...WGRFC...NWC... LAT...LON 32929142 32719065 32359058 31649080 30679185=20 30119266 29729348 29349521 30339573 31039453=20 32419374=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) .