Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon May 26 2025 22:04:34 AWUS01 KWNH 262204 FFGMPD TXZ000-270245- Mesoscale Precipitation Discussion 0322 NWS Weather Prediction Center College Park MD 604 PM EDT Mon May 26 2025 Areas affected...central TX Concerning...Heavy rainfall...Flash flooding possible Valid 262201Z - 270245Z Summary...Thunderstorms are expected to expand in coverage through the evening, possibly resulting in flash flooding over portions of central TX, including the TX Hill Country. Rainfall rates will vary but could be as high as 2-3 in/hr. Discussion...Local radar imagery over west-central TX at 2130Z showed a strong supercell over Menard County, tracking toward the southeast at 15-20 kt with additional cells feeding in from the south. These storms were located along an outflow boundary that extended from the the middle/upper TX coast, northwestward to a stationary front that was analyzed northeast from a triple point low near OZA. SPC mesoanalysis data showed the cells were within a very unstable environment with 3000-4000 J/kg MLCAPE, with roughly 5000 J/kg located southward, closer to the Rio Grande. VAD wind data from KEWX showed 850 mb winds of ~20 kt from the SE, emanating from a moisture rich environment where Blended TPW imagery showed 2+ inches of PWAT over south-central TX to the middle TX coast. These cells were forming out ahead of the southeastern edge of a an upper trough moving from NM into West TX. Given the largely uninhibited environment in place near/south of the outflow and in the vicinity of the triple point low along with larger scale forcing ahead of the upper trough, additional cells are likely across portions of the Edwards Plateau through 00Z. This type of environment favors supercells whose motions can be somewhat unpredictable due to storm scale influences, possibly leading to slower movement with enhanced rainfall efficiency with mesocyclones, allowing for at least a localized flash flood threat. Beyond the localized threat, there are indications for at least a modest increase in the low level flow beyond 00Z which could support a greater coverage of storms into the late evening and early overnight, with cell movement toward the east but potential upstream development leading to training and a greater flash flood risk. This threat for later in the night will continue to be monitored but there is at least a near-term flash flood concern from ongoing cells, mergers and slow movement. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6nCLXvX1ON5q8vsqdQjWWy8khzT-w9Erc4ysnjBnXk7n3cvDNzBg03A900Ayj5mfAgDA= X-hCITpU2h_rwqL2GsGAcjQ$ for graphic product... ATTN...WFO...EWX...FWD...SJT... ATTN...RFC...FWR...NWC... LAT...LON 31939871 31749784 31209721 30359723 29299789=20 29059920 29300076 29690141 30590150 31150080=20 31520001=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) .