AWUS01 KWNH 021526 FFGMPD VAZ000-NCZ000-SCZ000-022100- Mesoscale Precipitation Discussion 0572 NWS Weather Prediction Center College Park MD 1126 AM EDT Wed Jul 02 2025 Areas affected...Pee Dee region of SC through the Tidewater region of VA Concerning...Heavy rainfall...Flash flooding possible Valid 021525Z - 022100Z Summary...Showers and thunderstorms will gradually expand in coverage and intensify through the afternoon ahead of a front sagging slowly across the area. Rainfall rates at times this afternoon will likely exceed 2"/hr, leading to 2-3" of rain with locally higher amounts approaching 5". Flash flooding is possible. Discussion...Showers and thunderstorms are expanding across eastern/central North Carolina and far southern Virginia this morning. This convection is blossoming rapidly downstream of a slow moving, almost stationary, front which will eventually kick east as a cold front later this afternoon. The evolution of this front will be driven by a mid-level trough axis that will gradually swing east, and the overlap of the accompanying height falls with low-level convergence along the front will drive ascent to produce numerous thunderstorms through the afternoon. The environment into which this ascent will impinge will become increasingly favorable for heavy rainfall as 850mb SW flow of 20 kts resupplies PWs of 2-2.2 inches and MLCAPE of 1000-2000 J/kg northeastward. Additionally, this low-level inflow will equal or exceed the mean wind in the generally weakly forced environment, suggesting additional ascent through convergence. Rainfall rates so far this morning have been estimated to be above 2"/hr in the strongest cores, and a flash flood warning was just issued near Emporia, VA. While general cell motions have been modest on 0-6km mean winds of 15 kts, effective storm motions are much slower thanks to Corfidi vectors aligned increasingly anti-parallel to the mean flow and collapsed to just 5kts or less. This suggests that as the afternoon progresses and storms become more numerous, backbuilding/training of cells will become more common, lengthening the duration of heavy rainfall across many areas. Both the HREF and REFS suggest a moderate/high chance (40-70%) of rainfall rates exceeding 2"/hr, and with warm cloud depths rising to 13,000-14,000 ft, efficient warm rain processes may produce brief 3+"/hr rates. Through training, this has the potential (40-60% chance) of producing 2-3" of rain, with locally as much as 5" possible. FFG across this region is elevated (generally 3-4"/3hrs) so exceedance probabilities arelow, peaking at just 10-20%. This should generally limit the coverage of flash flood impacts today. However, the intensity of these rain rates, especially where training occurs or if they repeat across urban areas, could result in instances of flash flooding through the afternoon. Weiss ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...AKQ...CAE...GSP...ILM...MHX...RAH...RNK... ATTN...RFC...ALR...RHA...NWC... LAT...LON 37367652 37087614 36777590 36237548 35677540 35207583 34687690 34277766 34027809 33937846 34097911 34318003 34538030 34868032 35487990 36397902 37247742