Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Aug 02 2024 15:50:38 AWUS01 KWNH 021550 FFGMPD OHZ000-MIZ000-INZ000-022149- Mesoscale Precipitation Discussion 0779 NWS Weather Prediction Center College Park MD 1150 AM EDT Fri Aug 02 2024 Areas affected...southeastern Michigan through western Ohio Concerning...Heavy rainfall...Flash flooding possible Valid 021549Z - 022149Z Summary...Slow-moving downpours will gradually increase in coverage, resulting in several spots of 1-2 inch/hr rain rates through 22Z today. Flash flooding is possible - especially in urban/low-lying areas. Discussion...Recent radar/satellite imagery depicts deepening convection across far southeastern Ontario just east of the Detroit Metro area. These cores were rather slow-moving due to weak wind fields aloft, but were being supported by 1) forcing ahead of a mid-level wave over Indiana, 2) insolation/destabilization resulting in ~2000 J/kg SBCAPE in the pre-convective environment, and 3) weak confluence near a surface low over southern Michigan and a weak front extending through the area. Additional, yet more isolated areas of deepening convection were being depicted via satellite imagery across southern Michigan, Indiana, and far northwestern Ohio. Models and observations both suggest that convection will become more widespread with destabilization and cooling aloft/ascent overspreading the region through peak heating hours. Slow storm movement and 1.5-1.8 inch PW values should result in areas of efficient rainfall rates (exceeding 1 inch/hr at times). As convective coverage continues to expand, the rainfall will occur across areas of sensitive ground conditions in/near urban areas and across portions of Ohio that have experienced 1-4 inch rainfall totals (estimated per MRMS) near/north of I-70 in Indiana/Ohio. FFG thresholds are the lowest in these areas (around 1-1.5 inch/hr), and could be easily exceeded as cells materialize across that area this afternoon. Another area of concern is near Detroit, where similar FFG thresholds exist amid urbanized ground surfaces. Slightly higher FFGs exist across northwestern Ohio, which may mitigate a larger-scale flash flood threat this afternoon. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6MKWrXc_E7vQ8OnNdBtlYjViGIfiWsjyC9sdpbF8fuNddCEideDIQiIj9du8WHELxLp9= M1qpICyxY8Od7YQoXHEfSj4$ for graphic product... ATTN...WFO...CLE...DTX...GRR...ILN...IND...IWX...PBZ...RLX... ATTN...RFC...NCRFC...OHRFC...NWC... LAT...LON 43108246 41948242 41398224 40698183 39948217=20 39608324 39708486 41048564 42828499 43098338=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) .