Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jul 22 2025 23:35:56 AWUS01 KWNH 222335 FFGMPD TXZ000-NMZ000-230500- Mesoscale Precipitation Discussion 0780 NWS Weather Prediction Center College Park MD 735 PM EDT Tue Jul 22 2025 Areas affected...Portions of West Texas through the Cap Rock and into the High Plains of New Mexico Concerning...Heavy rainfall...Flash flooding possible Valid 222334Z - 230500Z Summary...Showers and thunderstorms will continue to develop and propagate slowly northward through this evening. Rainfall rates within stronger convection could exceed 2"/hr, at least briefly, leading to sub-hourly rainfall above 1 inch, and total rainfall of 1-2", locally higher. A few instances of flash flooding may result. Discussion...The regional radar mosaic this afternoon shows an expansion of reflectivity from the Edwards Plateau northward through the southern Cap Rock and into the adjacent High Plains of New Mexico. This convection is developing beneath a slowly departing upper low, and in response to moisture convergence as 850mb winds surge NW out of south-central Texas. The resultant ascent is acting upon improving thermodynamics, as a plume of PWs above 1.5 inches collocated with 2000-3000 J/kg of MLCAPE are resupplied by the 850mb inflow reaching 15-20 kts. While ascent is generally modest, the impressive thermodynamics in place are resulting in rain rates estimated via KMAF of more than 1.5"/hr and a few FFWs are already in place. Although the CAMs appear to be under-representing the current activity (although the 12Z FV3 may have the best handle), the overlap of supportive ascent into the favorable thermodynamics should support additional convective growth during the next few hours. This will result in an expansion of both coverage of thunderstorms, as well as an uptick of intensity, which leads to HREF neighborhood probabilities of 1"/hr rain rates peaking above 40% by 03Z. Thereafter, convection should begin to wane as the upper support ejects slowly away from the area and instability begins to fade due to both convective overturning and nocturnal stabilization. However, with storm motions expected to remain generally weak around 10 kts, and propagation vectors within a region of modest shear becoming more aligned into the moisture (and anti-parallel to the mean wind) this could result in regenerating cells repeating over some areas. Where repeating cells occur, the impressive rain rates could produce 1-2" of total rainfall, with locally higher amounts possible. Although rainfall across this area has been sparse the past 7 days according to AHPS, NASA SPoRT indicates that there are pockets of soil moisture above the 95th percentile with respect to the 0-40cm depth. This, combined with the natural vulnerability of the region due to terrain and soil types, suggests that any slow moving or repeating cells could lead to additional flash flooding through the evening. Weiss ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9Xe4Un90g4S3BE8srsXf1cgfUBGrRQOlAhc4pNh8GJnyCyYMte0mZtPxhPS7UCYgSF2_= lAddA94clwOhR4zbN5l4XGc$ for graphic product... ATTN...WFO...ABQ...EWX...LUB...MAF...SJT... ATTN...RFC...FWR...NWC... LAT...LON 34260233 33880174 33290139 31480118 31010120=20 30310137 29600191 29590245 29740313 30100359=20 30770416 31670451 32590469 33430445 34010381=20 34250300=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) .