Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon May 12 2025 01:31:43 AWUS01 KWNH 120131 FFGMPD TNZ000-ALZ000-MSZ000-ARZ000-120730- Mesoscale Precipitation Discussion 0256 NWS Weather Prediction Center College Park MD 930 PM EDT Sun May 11 2025 Areas affected...Northwest to Central MS...Central and Southern AL Concerning...Heavy rainfall...Flash flooding possible Valid 120130Z - 120730Z SUMMARY...Bands of showers and thunderstorms will continue into the overnight hours across areas of northwest to central MS along with adjacent areas of central and southern AL. Concerns for cell-training with heavy rainfall rates will pose a threat for scattered areas of flash flooding. DISCUSSION...The early evening GOES-E IR satellite imagery shows an elongated southeast/northwest axis of relatively cold-topped convection continuing to impact areas of central and southern AL up across central to northwest MS. The bands of convection which are linear in nature remain concentrated rather close to a frontal occlusion and are persisting within a moist and moderately unstable airmass with the aid of divergent flow aloft around the northeast flank of the deep layer trough/closed low over the lower MS Valley. MLCAPE values remain locally on the order of 1000 to 1500 J/kg with PWs of near 1.5 inches, and this coupled with some modest shear parameters has been supporting rainfall rates of 1 to 2 inches/hour with the stronger convective cores. There is a fair amount moisture convergence noted near the aforementioned frontal occlusion, and this coupled with the orientation of the convection with the deeper layer cyclonic flow should continue to yield linear convective structures that will be conducive for cell-training. The latest hires model guidance led by the HRRR and the RRFS collectively support as much as an additional 2 to 4 inches of rain going through 06Z (1AM CDT). The additional rains are expected to largely fall on areas that have seen recent rainfall, and thus with moist/wet antecedent conditions in place, there will continue to be a concern for scattered areas of flash flooding going into the overnight hours. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_S-7MAxSPke3GGhNJFikWZviEcceWn2e7YQ5cSsQEH7acwGWDohIE35xjVUZmDtlFu86= SMupNjXu7PuUylyaeQlBq80$ for graphic product... ATTN...WFO...BMX...JAN...MEG...MOB... ATTN...RFC...LMRFC...SERFC...NWC... LAT...LON 35148972 33888795 33428640 32868585 31808589=20 31348657 31368781 31568850 31848912 32498973=20 33519061 34799086=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) .