Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue May 27 2025 14:04:05 AWUS01 KWNH 271403 FFGMPD GAZ000-ALZ000-MSZ000-272000- Mesoscale Precipitation Discussion 0324 NWS Weather Prediction Center College Park MD 1002 AM EDT Tue May 27 2025 Areas affected...Southern and Eastern MS...Central AL...Northwest GA Concerning...Heavy rainfall...Flash flooding possible Valid 271400Z - 272000Z SUMMARY...Heavy showers and thunderstorms with some cell-training concerns will favor a threat for isolated to scattered areas of flash flooding going into the afternoon hours. DISCUSSION...A broken QLCS continues to advance off to the east this morning across portions of central and southern MS which is expected to advance downstream into areas of western and central AL through midday. However, recent radar and satellite trends already show an expansion of convection out ahead of the main QLCS activity, and in general, GOES-E IR satellite imagery shows an axis of cooling convective tops from central MS through west-central AL. The airmass will be destabilizing with time for many downstream areas of western and central AL and also into northwest GA going through the early afternoon hours. This coupled with the arrival of the convectively-enhanced shortwave traversing the lower MS Valley and interaction with a moist southwest low-level jet of 30+ kts nosing up across eastern MS through central AL should favor a general expansion of convection over the next several hours. PWs rising to over 1.75 inches and the destabilizing boundary layer will contribute to an uptick in rainfall rates. The relatively organized nature of the convective cells will be capable of yielding some rainfall rates of as much as 1.5 to 2 inches/hour which is supported by the 06Z HREF guidance. The overall convective footprint in satellite and radar imagery suggests a concern for cell-training going into the afternoon hours and some of the HREF guidance supports some rainfall totals of as much as 2 to 4+ inches going through mid-afternoon. Locally wet antecedent conditions from recent rainfall are reflected in lower FFG values, and the latest NASA SPoRT soil moisture data in conjunction with USGS streamflow data suggest sensitivities that will contribute to elevated runoff concerns. As a result, isolated to scattered areas of flash flooding will be possible where these heavier rainfall amounts occur over the next several hours. This will include potential for some urban flash flooding impacts. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8WU29EKXNicUu-9aXdUoIIrmzM1N2O9VFctLyEeVJxS7_ZzPrEWQw_zYF2NAO46_CMjs= M1uN4vGhum8uzBZu1aUiHpw$ for graphic product... ATTN...WFO...BMX...FFC...HUN...JAN...LIX...MOB... ATTN...RFC...ALR...ORN...NWC... LAT...LON 34568441 33578375 32708470 31878642 31178844=20 31038973 31429027 32369010 33158882 33998708=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) .