Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon May 12 2025 21:36:56 AWUS01 KWNH 122136 FFGMPD FLZ000-130035- Mesoscale Precipitation Discussion 0261 NWS Weather Prediction Center College Park MD 535 PM EDT Mon May 12 2025 Areas affected...Southeast FL Concerning...Heavy rainfall...Flash flooding possible Valid 122135Z - 130035Z SUMMARY...A band of heavy showers and thunderstorms will be approaching the urban corridor of southeast FL over the next couple of hours. As this activity crosses the region early this evening, and urban flash flood threat will exist. DISCUSSION...The latest GOES-E IR satellite imagery along with regional radar data shows a band of heavy showers and thunderstorms gradually crossing south FL, with the activity gradually encroaching on the I-95 urban corridor of southeast FL. The activity has been intensifying over the last hour with cooling convective tops noted, and this intensification trend is being facilitated by rather strong low-level moisture convergence and a moderate to strongly unstable airmass characterized by MLCAPE values of 1500 to 2000 J/kg. Meanwhile, it is very moist with PWs of 2.0 to 2.25 inches which is locally 3+ standard deviations above normal. Rainfall rates with the approaching convective band are expected to be very high considering a well-defined deep tropical airmass and robust instability. Some rainfall rates may be capable of reaching 2 to 3 inches/hour, with even some sub-hourly rainfall totals of as much as 1.5 inches in just 20 to 30 minutes possible. The convection is moving fairly slowly, but steadily off to the east, and should advance into the I-95 urban corridor of southeast FL from West Palm Beach down to Fort Lauderdale and the Miami metropolitan area within the next 1 to 2 hours. Given the high rainfall rates and relatively slow cell-motions, some rainfall totals by mid-evening could reach 3 to 4 inches. These additional rains coupled with local sensitivities from the rainfall that occurred this morning will pose a concern for flash flooding over the next few hours. However, even the high rainfall rates alone impacting the I-95 corridor of southeast FL this evening will drive a notable urban flash flood threat. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9Xg6sWsvXY4qY09efCUo_CbCtYAexn5UKyxJaBvLrn5bZK6xj1XsxcJh_nj2TJkmxa7e= UyEhxSk_Bll6Bru4kjXiKOs$ for graphic product... ATTN...WFO...KEY...MFL...MLB... ATTN...RFC...SERFC...NWC... LAT...LON 27468013 26727992 25888000 25238035 25388079=20 26308052 27428054=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) .