Flash Flood Guidance
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Issued by NWS
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746 AWUS01 KWNH 052154 FFGMPD TXZ000-060200- Mesoscale Precipitation Discussion 0229 NWS Weather Prediction Center College Park MD 553 PM EDT Sun May 05 2024 Areas affected...central to northeastern TX Concerning...Heavy rainfall...Flash flooding possible Valid 052152Z - 060200Z SUMMARY...Highly localized flash flooding may result over the next 3-5 hours from thunderstorms producing 1-2 in/hr rates atop saturated soils. Coverage of storms and their organization appears lower end, but recent heavy rainfall has increased the potential for runoff across portions of central to northeastern TX. DISCUSSION...Visible satellite imagery and lightning data indicated widely scattered thunderstorms over portions of central and eastern TX at 2145Z within a relatively clear region accompanied by 1000 to 2000+ J/kg MLCAPE over central to eastern/northeastern TX via the 21Z SPC mesoanalysis. These storms were forming within a zone of elevated convergence, in the wake of a departing upper level shortwave over the eastern TX/OK border. Despite the weak axis of low level forcing, subsidence behind the shortwave and an unfavorable upper level jet orientation makes this region of TX hostile to high coverage of thunderstorm development. Nonetheless, the zone of elevated convergence is expected to drift north over the next few hours with additional thunderstorm development appearing likely via an existing cell over Robertson County near Hearne (which produced 1.18 inches of rain in an hour ending 2134Z...via Wunderground.com), and agitated cumulus on visible imagery. Coverage of cells is likely to remain scattered in nature through the evening, but some slow movement of any robust cells that form may support 1-2 in/hr rainfall rates, on a highly localized basis. Dissipation of any thunderstorms should occur after sunset with the loss of daytime heating. Heavy rain over the past 10 days or so across central to northeastern TX, including 3 to 5+ inches over the past 24 hours to the west of I-35, has resulted in saturated soils and reduced infiltration capacity of additional rainfall. Any areas of renewed flash flooding that occur are expected to remain localized and likely lower end in magnitude. Otto ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...EWX...FWD...HGX...SHV...SJT... ATTN...RFC...WGRFC...NWC... LAT...LON 33239663 33109587 32889537 32539498 32109469 31429459 31159493 30829577 30929723 30959818 31289862 31829874 32599796 33229721