Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jan 30 2023 00:14:34 AWUS01 KWNH 300014 FFGMPD FLZ000-GAZ000-ALZ000-300513- Mesoscale Precipitation Discussion 0053 NWS Weather Prediction Center College Park MD 713 PM EST Sun Jan 29 2023 Areas affected...Portions of southern Alabama and southwest Georgia Concerning...Heavy rainfall...Flash flooding possible Valid 300013Z - 300513Z Summary...Isolated flash flooding will be possible through this evening with rain rates approaching 1-2"/hr at times. Isolated totals exceeding 3" are expected. Discussion...Southwesterly flow aloft and an embedded shortwave trough over Louisiana is providing the favorable large scale forcing for ascent over the MPD region. The mean southwesterly flow has allowed a surge of enhanced moisture to lift northeastward across the region characterized by precipitable water values in excess of 1.5" with isolated readings near 1.75" per the latest blended TPW product. These values are between 2-2.5 standard deviations above normal for this time of year. Regional radar continues to show overrunning precipitation with a stationary boundary draped along the Gulf Coast. The last several runs of the HRRR have been fairly consistent showing a stripe of higher rain totals through 06Z across parts of southern Alabama and southwest Georgia. The 18Z HREF showed a moderate signal for 6-hr QPF exceeding 3" with hourly totals between 1-2" possible for a few hours this evening. The much above normal moisture and favorable setup for repeating rounds (storm motions parallel to the mean flow) support this scenario, but the main limiting factors are the relatively dry/normal antecedent conditions (NASA SPoRT soil moisture 0-40 cm layer between 30-70 percent) and high flash flood guidance (1-hr 2.5"). Additionally, forecast guidance continues to show that any available instability will be further south toward the Gulf Coast. However, the prolonged period of moderate to occasional heavier downpours for several hours this evening could produce some isolated instances of flash flooding.=20 Taylor ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6UQip4voAKkHrOk6sqq-ad94TKLDGaaux_gpsKafwagkFJ69kzPFIpnHcRDSB9HGaFAA= 2MC9uuJSDPQR_mgcfwRNfsw$ for graphic product... ATTN...WFO...BMX...FFC...MOB...TAE... ATTN...RFC...SERFC...NWC... LAT...LON 32438562 32418389 32108327 31228350 30938488=20 30918627 31108694 31248723 32168700=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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .