Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed May 14 2025 20:29:54 AWUS01 KWNH 142029 FFGMPD PAZ000-MDZ000-VAZ000-WVZ000-OHZ000-150100- Mesoscale Precipitation Discussion 0270 NWS Weather Prediction Center College Park MD 429 PM EDT Wed May 14 2025 Areas affected...Northern WV...Southwest PA...Adj Eastern OH... Far Western MD...Far Northwest VA... Concerning...Heavy rainfall...Flash flooding possible Valid 142030Z - 150100Z SUMMARY...Slow moving, scattered to regionally dense narrow core convective cells capable of 1-1.5"/hr rates/totals over complex and recently saturated soils pose localized/focused flash flooding potential through evening. DISCUSSION...Recent GOES-E Visible loop shows broad area of congested cu/Tcu across northern WV into far SW PA/Garrett county MD become more numerous and increasing in vertical depth. Area has been confined to the north and northeast given prolonged stratus deck limiting peak heating. Surface Tds in the upper 50s/low 60s remains well above normal and with modest mid-level lapse rates, SBCAPEs have risen to 1500 J/kg to help develop/maintain convective vigor for the next few hours. GOES-E WV loop and RAP analysis denotes decaying upper-level low has sheared from NW to SE with core of vorticity across the Piedmont of NC/S VA with a secondary lobe back toward N OH, this has resulted in broad northeastward lift of the trof, but also resulted in slowing of the mid-level steering to less than 15-20kts. This should allow for strong cells to develop and collapse within a 1-2 hour period with locally intense rain-rates up to 1-1.5". While localized, the overall density of the narrow cores is fairly close in proximity, that as new development produces outflow and seeks out remaining unstable parcels for additional development, proximity may allow for isolated spots to have a second intense pulse with overall spotty totals perhaps reaching 2", with highest probability over NE WV into SW PA, as further north remains more stable given the lack of heating this afternoon. Given these intense rates over complex terrain naturally with lower FFG; recent heavy rainfall in spots over the last day or so as further reduced the capacity of soils, with increased run-off likely. As such, scattered incidents of flash flooding are considered possible through late evening/early overnight as instability is exhausted. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5y3GBp-wWsDsjYStz99xzTB4Jsc7IQJSYXpbRjk44mgYA7joYS-mC4A8IyYPKSR2rl-D= _86UJu0HiFYEnBlUKUgByVg$ for graphic product... ATTN...WFO...LWX...PBZ...RLX...RNK... ATTN...RFC...MARFC...OHRFC...NWC... LAT...LON 40788042 40427977 39717944 39077858 37977931=20 37978049 38858081 39368114 39778148 40568117=20 =20=20=20=20=20=20=20=20=20=20=20=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .