


Flash Flood Guidance
Issued by NWS
Issued by NWS
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525 AWUS01 KWNH 040527 FFGMPD TXZ000-041030- Mesoscale Precipitation Discussion 0584 NWS Weather Prediction Center College Park MD 126 AM EDT Fri Jul 04 2025 Areas affected...central TX Concerning...Heavy rainfall...Flash flooding likely Valid 040525Z - 041030Z Summary...Areas of flash flooding will be likely across central TX overnight with very heavy rainfall expected. Hourly rainfall in excess of 2 to 3 inches seems reasonable given the environment and localized 6-hr totals over 6 inches will be possible. Some flash flood impacts could be significant, especially considering sensitive terrain over portions of the region. Discussion...05Z regional radar mosaic over central TX showed an ongoing area of thunderstorms with a few areas of very efficient rainfall resulting from embedded training. As of 05Z, some of the heaviest hourly rainfall (2 to 3 inches per MRMS) was occurring over Bandera and San Saba counties. Another area of training was found just southeast of San Angelo along US 87, tied to a remnant MCV circulation (related to the remains of Barry`s mid-level circulation), located between SJT and JCT and embedded within a broader mid-level trough that extended NNW into eastern CO. The region was located within an extremely moist environment containing 2.0 to 2.5 inches of PW with contributions from the Gulf of America and tropical east Pacific clearly evident on layered PW imagery. Low level southerly winds sampled by area VAD wind plots at 850 mb were 20-30 kt and these winds are expected to maintain through the overnight with some subtle strengthening possible over the next couple of hours. The upper trough and remnant mid-level circulation over central TX is expected to slowly advance east while low level convergence continues to focus from the TX Hill Country, northward to the I-20 corridor. Terrain enhancement into the Hill Country and low level convergence at the leading edge of the stronger low level flow will set up favorably with the mean steering flow from the southwest to support areas of training. The tropical airmass will be capable of 2 to 3+ inches of rain in an hour and localized totals over 6 inches in a 6 hour period may also occur. These areas of heavy rainfall are expected to result in a few areas of flash flooding through the overnight, some of which may become locally significant. Otto ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...EWX...FWD...SJT... ATTN...RFC...FWR...NWC... LAT...LON 33139936 32779820 31759771 30119833 29209929 29330030 29950076 31250063 32340033