Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Oct 25 2025 19:25:55 AWUS01 KWNH 251925 FFGMPD TXZ000-260115- Mesoscale Precipitation Discussion 1212 NWS Weather Prediction Center College Park MD 323 PM EDT Sat Oct 25 2025 Areas affected...Central TX Concerning...Heavy rainfall...Flash flooding possible Valid 251923Z - 260115Z SUMMARY...Heavy showers and thunderstorms will be redeveloping and gradually expanding in coverage going through the early evening hours. Some cell-training concerns and locally high rainfall rates coupled with recent moistening of soil conditions may foster localized areas of flash flooding. DISCUSSION...The early-afternoon GOES-E visible satellite imagery in conjunction with surface data shows the boundary layer across central TX gradually destabilizing as a cold front approaches from the west. This is evidenced by an expanding CU/TCU field along with a southwest/northeast oriented axis of showers and thunderstorms that has developed from KBBD to just north of KMNZ. Solar insolation combined with fairly steep mid-level lapse rates have allowed MLCAPE values across the eastern portions of the TX Hill Country to increase to as much as 1000 to 1500 J/kg. This coupled with moderately strong effective bulk shear values (30 to 40 kts) and arrival of deeper layer ascent associated with jet energy rounding the base of the southern Plains upper trough/closed low should favor an uptick the coverage of convection over the next few hours across central TX. Areas a bit farther off to the east involving eastern TX are much more stable in the wake of the early morning QLCS, and the latest RAP analysis shows this region struggling to destabilize, so much of the heavy rainfall threat in the near-term should be across portions of the TX Hill Country up into the TX Triangle region. This is where better low-level convergence ahead of the front and interaction with unstable southwest flow will be noted. Some cell-training concerns are going to be possible with the convection given the linear nature of the activity along with alignment close to the deeper layer steering flow. Rainfall rates will be capable of reaching 1.5 inches/hour with the stronger storms, with some localized 2 to 4 inch rainfall totals possible where the better cell-training occurs through early this evening. The latest HRRR and RRFS guidance supports this, but the RRFS is notably wetter and probably too wet given the modest PW environment (~1.25 inches) and moisture transport regime. Given the rainfall potential and locally moistened soil conditions from last night's rainfall, there may be a localized threat for some flash flooding heading through early this evening. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5abBr_tUvcIQ38IHIAQqo8ktwJT7BlAcXgbR9Vm24rUZLEPHbahC6jGXaDGXn3OYNIZ8= BGMPcugFs-TiQJJXnGwgWGI$ for graphic product... ATTN...WFO...EWX...FWD...SJT... ATTN...RFC...FWR...NWC... LAT...LON 32749635 32559589 32159571 31509585 30719681=20 30239838 30279977 30580014 30910011 31219959=20 31499898 31799842 32629718=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) .