Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Feb 28 2024 09:33:34 AWUS01 KWNH 280933 FFGMPD PAZ000-MDZ000-VAZ000-WVZ000-OHZ000-KYZ000-INZ000-281500- Mesoscale Precipitation Discussion 0073 NWS Weather Prediction Center College Park MD 433 AM EST Wed Feb 28 2024 Areas affected...portions of the upper Ohio Valley and surrounding areas Concerning...Heavy rainfall...Flash flooding possible Valid 280931Z - 281500Z Summary...Fast-moving convection across Indiana/Kentucky will migrate through the discussion area over the next 3-6 hours. A modest increase in flash flood potential is expected, though the overall threat is expected to remain isolated at best. Discussion...Mid-level ascent across the Lower Ohio Valley has finally interacted favorably with seasonably high warmth/moisture located across much of the Ohio Valley to promote development of bands of convection generally from near Dayton, OH southwestward to near Paducah. The storms were embedded in a warm sector characterized by around 1000 J/kg MUCAPE (per SPC Mesoanalyses) and 70-80 knot mean westerly flow between 850-300mb, promoting fast storm motions (around 50 knots). Despite the quick forward speeds, a few structures were oriented favorably for localized training/repeating and rain rates estimated at around 1 inch/hr per MRMS. The storms are currently located atop areas of mostly 1.5-2 inch/hr FFG thresholds, suggestive of a very isolated flash flood threat in the near term (through 1030Z). Over time, however, expanding convective coverage and movement toward more moist soils and generally more sensitive ground conditions (i.e., FFGs at around 1 inch/hr into Ohio and West Virginia) suggests a gradual uptick in flash flood potential from 1030Z-1500Z. Hillier terrain and sensitive low spots could be the focus for this flash flood risk, especially if those spots happen to underlie training convection that can foster better rain rates for an hour or two. Despite more favorable ground conditions with eastward extent, the fast storm motions should still mitigate the overall risk. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8kfzGTwwa-vDp_FTodeE57L36OKM-NlrEuldRUODM0VWiK58kdCbg_rrOlmyDlocu2UX= JEMmd6Hx2qrZP92RNFug-fE$ for graphic product... ATTN...WFO...CLE...CTP...ILN...JKL...LMK...LWX...PBZ...RLX... RNK... ATTN...RFC...MARFC...OHRFC...NWC... LAT...LON 40788179 40748014 40287859 39567830 38567926=20 38098073 37698395 37758576 38978526 40498354=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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .