Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Mar 09 2024 06:10:47 AWUS01 KWNH 090610 FFGMPD FLZ000-GAZ000-ALZ000-091200- Mesoscale Precipitation Discussion 0092 NWS Weather Prediction Center College Park MD 109 AM EST Sat Mar 09 2024 Areas affected...Southern AL...Southwest to Central GA...Florida Panhandle... Concerning...Heavy rainfall...Flash flooding possible Valid 090610Z - 091200Z SUMMARY...A few more hours of potential back-building and training thunderstorms capable 2"/hr rates and isolated spots of flash flooding or re-aggravation of ongoing flooded/saturated grounds. DISCUSSION...06z surface analysis denotes a pair of surface waves along a relatively stationary frontal zone from central AL back toward southeast LA. A very subtle low to mid-level wave is riding northeastward along this boundary at the lead edge of a mid to upper level speed max ahead of the positively tilted synoptic long wave over the mid to lower Mississippi River Valley. Spurred by weak divergence aloft, this 925-850 wave is providing a short-term increase in warm advective response off the high Theta-E air mass of the central Gulf where Tds remain in the low 70s. CIRA LPW notes that the sfc-850 layer is highly anomalous and near 1" total across SE LA into southern AL ahead of this front. Combined with confluent 850-700 (.5-.66") and exiting pocket of 700-500 (.25-.33) values combine to 1.75-2" total PWat across Mobile Bay. Modestly unstable MLCAPEs to 1500 J/kg will provide ample buoyancy for the warm sector for stronger efficient thunderstorms with rates of 2"/hr likely. However, the overall flow continues to become increasingly unidirectional through depth, limiting convergence for convective initiation. Surface convergence has been weak enough to spur occasional cells/weak clusters that train across the warm sector until reaching the warm front that cross SE AL into the eastern FL Panhandle. Afterward, isentropic ascent is strong with 50+kt of ascent over the cooler/stable air in GA, but providing strong moisture flux for broad shield precipitation. While rates decrease to .5"/hr with some embedded convective elements occasionally up to 1" randomly scattered through GA...adding to moderate rainfall that has already fallen over the last few hours. As the mid-level wave/upper-level speed max moves through, height-falls will increase movement of the cold front from west-east reaching the western FL panhandle by 12z. As such, streaks of 2-4" totals in short 1-2hr durations remain possible across the warm sector in S AL/FL panhandle with broad 2-3" of shield precip across areas of GA which may still result in flooding, but less likely flashy in nature. In either scenario, flooding is considered possible though 12z. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4T5Wr2Tc4fCVpqOpOHbTuKC3NdTfzYZfod052jOpIXNkFfb7btoA3deLods_Oa8zxdvk= mk9mLZw-1uzbegfAv1U6EP8$ for graphic product... ATTN...WFO...BMX...FFC...MOB...TAE... ATTN...RFC...LMRFC...SERFC...NWC... LAT...LON 33878368 33728300 33238250 32678235 31998275=20 31608325 31238371 30358496 30208724 30348824=20 30968820 31408750 32008652 32708559 33108518=20 33628438=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) .