####018000715#### PENA01 KWNH 141200 @UHPISF000CN MPDSUM@V2.0@0101700060@12140525@@0NMCGPHMPD ]p@!' `' ` @ & B7)p&PNAM02@@6C}~~~~~~|||{{{{z{z{|y{{{z|@@C@@C@@0268 @@d&MESOSCALE DISCUSSION SUMMARY GRAPHIC @@d& OF ALL VALID MESOSCALE DISCUSSIONS AT @@d& TIME OF PRODUCT CREATION:@@d& ISSUED 05/14/2025 1730Z @@ dNOAA/NWS/NCEP@@d WEATHER PREDICTION CENTER @@d FOR COLOR VERSION SEE: @@d WWW.WPC.NCEP.NOAA.GOV @####018003561#### AWUS01 KWNH 141734 FFGMPD VAZ000-NCZ000-142300- Mesoscale Precipitation Discussion 0269 NWS Weather Prediction Center College Park MD 133 PM EDT Wed May 14 2025 Areas affected...Eastern North Carolina and Virginia Concerning...Heavy rainfall...Flash flooding possible Valid 141733Z - 142300Z Summary...Showers and thunderstorms will increase in coverage through the afternoon and lift slowly northeast. Rainfall rates may exceed 2"/hr at times within this convection, leading to pockets of 2-3" of rain or more. This could cause flash flooding, especially over urban areas or more sensitive soils. Discussion...The regional radar mosaic this afternoon shows rapidly expanding coverage of showers and isolated thunderstorms from the Piedmont of North Carolina through the Tidewater Region of Virginia. This convection is blossoming in response to increased ascent through a variety of forcing including a wave of low pressure and accompanying stationary front, the Piedmont Trough, and a potent shortwave/vorticity maxima noted on the GOES-E WV imagery. Together, these are producing deep layer ascent into favorable thermodynamics characterized by PWs of 1.4-1.5 inches, around the 90th percentile at both KMHX and KWAL, with MLCAPE measured by the SPC RAP analysis now exceeding 1500 J/kg. At the same time, a plume of higher sfc-850mb and 850-700mb noted in the CIRA LPW product is surging across Cape Fear, and this will additionally enhance moisture/thermodynamics as it lifts northward on minimally veered SW sfc-500mb flow. Rainfall rates within this developing convection have already been estimated via KRAX and KAKQ to exceed 1.5"/hr. As the aftn progresses, shower and thunderstorm coverage will likely become more widespread as reflected by available CAM simulated reflectivity, with intensity also peaking later this aftn and into the evening. The HREF and REFS rainfall rate probabilities feature a 60-80% chance of exceeding 1"/hr, and about a 20% chance of exceeding 2"/hr. Although mean 0-6km winds should remain modestly progressive at 15-20 kts to the northeast, Corfidi vectors collapse to around 5 kts, which when combined with a surge of greater thermodynamics approaching from the south suggests short term training/backbuilding is probable to enhance the duration of these rain rates. This storm motion collapse could also occur along the sea breeze or stationary front, providing additional impetus for heavy rainfall accumulations, locally exceeding 2-3" of rain. Much of this region has been wet the past 7 days as reflected by AHPS rainfall departures of 150-300% of normal, leading to 0-40cm soil moisture that exceeds the 98th percentile. This has compromised FFG to as low as 1"/1hr and 1.5"/3hrs, lowest across southeast and south-central VA which is where HREF 3-hr FFG exceedance probabilities are highest. Any short term training of these intense rain rates, especially across these more sensitive soils of VA, or atop any urban areas, could result in instances of flash flooding into this evening. Weiss ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...RNK... ATTN...RFC...MARFC...SERFC...NWC... LAT...LON 38067718 38007684 37817658 37347631 36787594 36537599 36167620 35757654 35447697 35217753 35107807 35427858 35677902 35877944 36027975 36257993 37017938 37667847 37927776