Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jul 10 2025 18:04:25 AWUS01 KWNH 101803 FFGMPD VAZ000-NCZ000-WVZ000-SCZ000-TNZ000-110000- Mesoscale Precipitation Discussion 0636 NWS Weather Prediction Center College Park MD 201 PM EDT Thu Jul 10 2025 Areas affected...Central Appalachians through the Carolina Piedmont Concerning...Heavy rainfall...Flash flooding possible Valid 101800Z - 110000Z Summary...Scattered instances of flash flooding expected across the interior southern Mid Atlantic into the Carolina Piedmont. Discussion...Visible satellite this afternoon continues to depict a some hindrance of typical diurnal heating with scattered to widespread cloud cover extending south to north across the Carolinas into the Delmarva. Back into the interior southern Mid Atlantic, pockets of clearing can be seen over the western Carolinas with some enhanced cumulus development, mainly along and west of I-85. Better solar insulation materialized across far southern WV into southwest VA earlier today allowing for scattered convective development where destabilization was maximized. The expected convective cadence this afternoon is for slow clearing to eventually give way to regional destabilization allowing scattered shower/thunderstorm pulses to initiate within the outlined area.=20 Sufficient buoyancy and reputable PWATs hovering between 1.8-2.1" will present a reasonable environment for scattered heavy convective cores later this afternoon, leading to rates between 1-2 inches/hour, on average. A few stronger cells across the Carolina Piedmont could very well push closer to 2-3 inches/hour however, especially in proximity to a defined surface trough bisecting the region longitudinally based off the latest surface analysis. This will put areas across the central portions of NC/SC at the greatest threat for heavy rain and flash flooding and overlapping areas that has seen their FFG's lower as a result of previous convective impacts.=20 Recent hi-res deterministic models have inferred on the threat of scattered convective activity materializing by mid-afternoon, carrying into the early evening before waning as the activity will be subject to mainly thermodynamic processes with a weak kinematic aid of a meager shortwave rippling eastward out of the Tennessee Valley. Shear will be negligible today which correlates to more pulse convective modes and slower storm motions once activity initiates. Any steering pattern is weak, but will offer a slow advancement eastward as we move through the afternoon. Once we reach sunset, expecting convection to slowly dissipate over the eastern Carolinas with the loss of diurnal heating considering the overall environmental evolution. This will leave a window of 6-8 hrs for the greatest convective threat, enough for HREFbm output of 2-4+" scattered over the western Carolinas down through the Piedmont. The combination of slower mean storm motions and wet antecedent conditions over much of western and central NC down through the central SC Piedmont offers the risk of scattered flash flood instances with the greatest threat within more urbanized zones. Given lack of a true kinematic forcing and environmental bulk shear, organized multi-cell clusters will be less common, thus limiting the threat to flash flooding possible with more isolated to scattered signals across portions of the southern Mid Atlantic. Kleebauer ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5_KcLxHU90ogeDWr7pkPN2WBbovdm8FegwO1iHnEPRhZSjnD0Bd8qNEsJkYqoryaokfZ= 8-OwaKrvjT0G-P8PzOXpOG0$ for graphic product... ATTN...WFO...AKQ...CAE...GSP...ILM...LWX...MRX...RAH...RLX... RNK... ATTN...RFC...ALR...ORN...RHA...TIR...NWC... LAT...LON 38527878 38117846 37187834 36647827 36427825=20 36017830 35697834 35437843 35117863 34737900=20 34527919 33987959 33787982 33648008 33588038=20 33558059 33528087 33518109 33608137 33728156=20 33908176 34068189 34238201 34398217 34548235=20 34808247 35238278 35688285 36018270 36238247=20 36418229 36628230 36808236 37028240 37248217=20 37458188 37638162 37728133 37868113 37968096=20 38058083 38218041 38267974 38427930=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) .