Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Dec 09 2024 17:06:42 AWUS01 KWNH 091706 FFGMPD MSZ000-LAZ000-092304- Mesoscale Precipitation Discussion 1168 NWS Weather Prediction Center College Park MD 1206 PM EST Mon Dec 09 2024 Areas affected...Southeast LA and Far Southern MS Concerning...Heavy rainfall...Flash flooding possible Valid 091704Z - 092304Z SUMMARY... A narrow band of showers and storms training across southeast LA into MS containing hourly rainfall rates up to 2" at times could produce areas of flash flooding through this afternoon. Any flash flood risk is expected to be localized and confined to urbanized locations. DISCUSSION... Upper shortwave crossing over the western Gulf Coast, as evident by GOES-16 mid-level WV, ahead a of deeper positively-tilted longwave trough extending from the Upper Midwest to the central Great Basin are aiding in enhance lift along the central Gulf Coast. Strong west-southwest flow at the mid and upper levels along the central and western Gulf Coast are maintaining a moist environment with analyzed PWs of 1.7-1.9" centered across south-central and southeast LA. These PW values also near the 90th climatological percentile per the 00z ECENS. Uniform west-southwest flow through the column will also support the training potential into this afternoon until the better forcing shifts eastward by this evening. Instability will be a limiting factor as MUCAPE remains around 500-1000 J/kg, which for this part of the country struggles to produce rainfall rates above FFG. 3-hour FFG of 3-5" exists across much of the region, but are lower near Baton Rouge and Lafayette due to prior rainfall. 12z HREF and 15z HRRR guidance seem to have an ok handle on current trends and highlight a low chance for exceeding 3" per 6 hours by this evening within the MPD area. If training occurs over low-lying or urban regions for an extended period, localized flash flooding is possible. Snell ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9Ua6quaahsrqkzhmkj3WqcRhB5bVObQ6f4qoNdWMD4P1mWRNdlQNBAVGh26W39UYyqpt= AzvV1okY2UYluhPW0fgXzpg$ for graphic product... ATTN...WFO...LCH...LIX...MOB... ATTN...RFC...LMRFC...NWC... LAT...LON 30938954 30748893 30318894 29998953 29569081=20 29349194 29679223 30229177 30769057=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) .