


Flash Flood Guidance
Issued by NWS
Issued by NWS
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205 AWUS01 KWNH 301305 FFGMPD LAZ000-TXZ000-301715- Mesoscale Precipitation Discussion 1031 NWS Weather Prediction Center College Park MD 904 AM EDT Sat Aug 30 2025 Areas affected...eastern TX into southwestern LA Concerning...Heavy rainfall...Flash flooding likely Valid 301303Z - 301715Z SUMMARY...Heavy to extreme rain rates over 3 in/hr are expected to occur within localized pockets over portions of eastern TX and southwestern LA over the next few hours. Areas of flash flooding are likely to continue through 17Z. DISCUSSION...1245Z radar imagery over the lower Sabine River Valley showed a small cluster of thunderstorms west and northwest of LCH with 3 Wunderground observation stations reporting 3+ inches of rain in an hour two stations showing 5 inches in an hour through 12Z. Thunderstorm coverage was expanding NNW from southwestern LA into portions of eastern TX along an elevated (925-850 mb) convergence axis with low level flow intersecting the boundary from the west. Some of the "strongest" low level flow was located just south of the DFW Metroplex and over southwestern LA with about 10-15 kt oriented nearly perpendicular to the elevated convergence axis with mean layer winds directing cells slowly toward the southeast. SPC mesoanalysis data from 12Z showed MUCAPE values of 500-1500 J/kg coincident with PWATs of 2.1 to 2.3+ inches. Short term forecasts from the RAP show the low level flow maintaining over the next few hours but with gradual weakening through 17Z which may act to disrupt organization late this morning. However, the environment will remain supportive of highly efficient rainfall production until then with pockets of extreme rain rates possible (3+ in/hr) and localized storm totals in excess of 5 inches through 17Z. Areas of flash flooding will be likely and trends will be monitored for additional MPDs as needed later this morning. Otto ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...FWD...HGX...LCH...SHV... ATTN...RFC...FWR...ORN...TUA...NWC... LAT...LON 33749671 33139547 31009322 30339289 29939296 29649337 29589393 29769442 30549520 31689627 32679726 33539748