Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Sep 28 2025 22:56:36 AWUS01 KWNH 282256 FFGMPD TXZ000-NMZ000-290455- Mesoscale Precipitation Discussion 1152 NWS Weather Prediction Center College Park MD 655 PM EDT Sun Sep 28 2025 Areas affected...Central and Southern NM...Southwest TX Concerning...Heavy rainfall...Flash flooding likely Valid 282255Z - 290455Z SUMMARY...Clusters of heavy showers and thunderstorms will persist through the evening, bringing a likelihood of additional scattered flash flooding, particularly impacting burn scar areas and arroyos. DISCUSSION...Late-afternoon GOES-E IR satellite imagery shows cold-topped convective clusters affecting many areas of central and southern New Mexico, with the most concentrated and coldest cloud top temperatures focused over southwest Texas in the last couple of hours. Strong upper-level divergence continues over the region as an upstream upper-level trough approaches from the west. This deeper layer forcing and ascent continue to interact favorably with a moderately unstable airmass, sustaining the convection. In fact, the latest RAP analysis indicates MLCAPE values of 1000 to 1500+ J/kg extending from southwest Texas northward across central New Mexico. Concurrently, effective bulk shear values reaching 30 to 40 knots are contributing to locally well-organized convective cells with strong updrafts and heavy rainfall rates. Sufficient dynamical forcing and diurnally enhanced instability will continue into the evening, maintaining convective clusters across the region with localized heavy rainfall. Supporting this will also be corridors of stronger low-level moisture convergence which over the last couple of hours have been rather notable across southwest Texas and into far southern New Mexico. PW values remain generally 1.5+ standard deviations above normal. Given these environmental conditions, rainfall rates with stronger convective cells are likely to continue reaching 1 to 2 inches/hour. The latest high-resolution CAMs suggest additional localized rainfall totals of 2 to 4+ inches through late this evening where some cell-merger and terrain-anchored convection materializes. These additional rains are expected to cause further scattered flash flooding throughout the evening. Normally dry washes and arroyos, as well as burn scar locations, will remain particularly vulnerable to flash flooding impacts over the next several hours. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!80FISsy1HC6iJi4VgvFYaDVf84S-OPSaSiuL7dSbLws1D55ZljEYSRH6-dGYuZ7TsEEE= yJZ8FivTYyinzpi6-yYwDQg$ for graphic product... ATTN...WFO...ABQ...EPZ...MAF... ATTN...RFC...FWR...STR...TUA...NWC... LAT...LON 36170513 35400449 33510435 32150431 31230400=20 30360370 29960395 29900470 30540549 30820584=20 31440642 32380699 33130776 34010801 35210770=20 36050661=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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .