


Flash Flood Guidance
Issued by NWS
Issued by NWS
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526 AWUS01 KWNH 090548 FFGMPD MDZ000-VAZ000-NCZ000-091015- Mesoscale Precipitation Discussion 0626 NWS Weather Prediction Center College Park MD 148 AM EDT Wed Jul 09 2025 Areas affected...central to southeastern VA into southern DelMarVa Peninsula Concerning...Heavy rainfall...Flash flooding possible Valid 090547Z - 091015Z Summary...A threat of flash flooding will continue across portions of central to southeastern VA and possibly into the southern DelMarVa Peninsula through 09-10Z. Rainfall rates of 1-2 in/hr (locally higher possible) and additional totals of 2-4 inches are expected. Discussion...Local radar imagery at 0520Z showed a region of thunderstorms extending west-east from central VA to just west of the Chesapeake Bay. MRMS has been matching local gauge reports fairly well over the past 2-3 hours in showing peak hourly rainfall totals in the 1-2 inch range. An outflow boundary was noted to be pushing south of the Richmond/Petersburg metro but additional storms to the west were likely being aided via a southwesterly axis of low level moisture feeding directly into the region at 20 kt/isentropic ascent, beneath weakly diffluent flow aloft. MLCAPE trends have come down significantly over the past 3 hours with 05Z SPC mesoanalysis data showing less than 500 J/kg MLCAPE in place over most of VA. However, relatively steep lapse rates in the 850-700 mb layer (6.5-7.5 C/km) were contributing to elevated instability of up to 1000 J/kg across much of the region. Thunderstorms are expected to continue advancing east over the next few hours but with some southward translation due to cold pools and propagation into the inflow. While weakening of convective intensity is anticipated overall by 09/10Z, flash flood potential will continue to linger from 1-2 in/hr rainfall rates (locally higher possible) and the potential for an additional 2-4 inches over the next 3-5 hours. If storms are able to survive, they will bring potential flash flood impacts to the Hampton/Norfolk/Virginia Beach regions of southeastern VA, although recent available hires models do not support storms maintaining significant intensity that far east. Otto ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...AKQ...RNK... ATTN...RFC...ALR...RHA...NWC... LAT...LON 38137536 37817510 37257534 36547584 36507701 36637865 37227873 37637750