Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat May 03 2025 18:49:19 AWUS01 KWNH 031849 FFGMPD NCZ000-GAZ000-TNZ000-KYZ000-ALZ000-MSZ000-040048- Mesoscale Precipitation Discussion 0215 NWS Weather Prediction Center College Park MD 248 PM EDT Sat May 03 2025 Areas affected...Portions of the TN Valley Concerning...Heavy rainfall...Flash flooding possible Valid 031848Z - 040048Z SUMMARY...Bands of heavy showers and thunderstorms will be impacting portions of the TN Valley going through the afternoon and evening hours. Some localized potential for flash flooding will exist where the stronger and more organized storms occur, and especially with somewhat moist antecedent conditions. DISCUSSION...The early afternoon GOES-E visible satellite imagery shows convection developing and expanding in coverage across areas of eastern MS up through northern AL and into middle TN. Despite some cloud cover which has tempered the boundary layer destabilization process, there has been a sufficient level of diurnal heating to foster MLCAPE values of near 1000 J/kg across eastern MS and into northern AL, with lesser values noted up across middle TN. A cold front meanwhile continues to edge off to the east as a deeper layer trough and closed low pivots across the middle MS and lower OH Valley region. The pooling of moisture and instability ahead of this front this afternoon and evening should continue to favor a general increase in the coverage of convection, although the activity should tend to be oriented in linear bands aligned with the deeper layer southwest flow across the broader TN Valley region. Additional boundary layer instability through solar insolation coupled with fairly strong moisture convergence near the front should help yield pockets of heavier rainfall rate potential that may reach as high as 1 to 2 inches/hour. PWs are seasonably moist with values of 1.2 to 1.4 inches and there is a sufficient level effective bulk shear (30 to 40 kts) to favor some level of stronger updrafts/organization for some of these heavier rainfall rates to materialize. Hires model solutions generally favor as much as 2 to 4 inches of rain with the stronger storms and where any brief cell-training occurs given the linear nature of the convection. Some localized 1-hour and 3-hour FFG exceedance may occur as a result, and some locations over the broader TN Valley region did see heavy rainfall yesterday which has led to some moistening of the soils along with higher streamflows. As a result, some localized potential for flash flooding will exist going through the afternoon and evening hours. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7EtQmXZXqbXR8RUP2LHqsVL0HqYhd2s2e84_W4kNxEHm-KM7VjZWFeZZPBRNpRDWthBE= n93eO-qD7O1_3LEHfi4YQVI$ for graphic product... ATTN...WFO...BMX...FFC...GSP...HUN...JAN...JKL...LMK...MEG... MOB...MRX...OHX... ATTN...RFC...LMRFC...OHRFC...SERFC...NWC... LAT...LON 36798491 36768379 36238345 35048410 33338559=20 32598673 32248813 32508895 33188908 34398750=20 36038601=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) .