Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Jun 06 2025 18:17:39 AWUS01 KWNH 061817 FFGMPD NYZ000-NJZ000-PAZ000-DEZ000-MDZ000-VAZ000-DCZ000-WVZ000-OHZ000-KYZ000-07001= 5- Mesoscale Precipitation Discussion 0382 NWS Weather Prediction Center College Park MD 216 PM EDT Fri Jun 06 2025 Areas affected...Central Appalachians into the Northern Mid-Atlantic Concerning...Heavy rainfall...Flash flooding likely Valid 061815Z - 070015Z SUMMARY...Showers and thunderstorms will continue to locally expand in coverage through the afternoon and early evening hours. Isolated to scattered areas of flash flooding are likely from heavy rainfall rates and locally wet antecedent conditions. DISCUSSION...The early afternoon GOES-E visible satellite imagery along with dual-pol radar shows scattered to locally broken areas of heavy showers and thunderstorms already impacting southeast OH, much of WV, western MD and also southwest to northeast PA. Strong boundary layer heating continues locally which has allowed for MLCAPE values to rise to as much as 1000 to 1500 J/kg, with the better instability noted across southeast PA through northern NJ. However, secondary areas of 1000+ J/kg CAPE values are also noted across the western slopes of the central Appalachians in the wake of earlier convection. Heavy showers and thunderstorms will generally continue to advance east off the terrain of the Appalachians and Blue Ridge over the next few hours and get into at least the Piedmont areas of the northern Mid-Atlantic. There are some question marks about the I-95 corridor where some pockets of larger scale subsidence are noted given proximity of a surface low center off the Delmarva, but as this low pulls away, and additional surface heating takes place over the next few hours, the I-95 corridor from northern VA through northeast MD, southeast PA, and into central and northern NJ may also get into these areas of thunderstorms. Radar imagery shows a band of strong thunderstorms with high rainfall rates focused from near Harrisburg, PA down through Martinsburg, WV, and this band is associated with some evidence of a weak MCV/shortwave impulse. Ongoing recover of instability farther west over the central Appalachians and the western slopes of the terrain is occurring out ahead of a cold front, but with additional upstream shortwave energy approaching along with the influence of orographics, convection will be reloading across these areas going through early this evening. Rainfall rates with the stronger storms across the entire region will likely be 1 to 2 inches/hour, but with some additional spotty rainfall totals of as much as 2 to 3 inches going through early this evening. Given the impacts over areas that are already very moist on the ground, and also the concern for some urban impacts, isolated to scattered areas of flash flooding will generally be likely. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7mz0OZtuNSlhagVe1Mni9j0Yb8V2ZrpBiRGIRUqIZzkSOPuBHLPYm6d7xOoThzzJ42Dh= QwNakitSH09JOftHuUGCkyg$ for graphic product... ATTN...WFO...BGM...CLE...CTP...ILN...JKL...LWX...OKX...PBZ... PHI...RLX...RNK... ATTN...RFC...RHA...TAR...TIR...NWC... LAT...LON 41987566 41777473 41327390 40537389 39747517=20 38767691 38047841 37438006 37228239 38398348=20 39318287 40188147 41358002 41737872 41957725=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) .