Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jun 14 2023 13:07:32 AWUS01 KWNH 141307 FFGMPD GAZ000-ALZ000-141847- Mesoscale Precipitation Discussion 0480...Corrected NWS Weather Prediction Center College Park MD 906 AM EDT Wed Jun 14 2023 Corrected for Typo in graphic Areas affected...Central AL...South-Central GA Concerning...Heavy rainfall...Flash flooding possible Valid 141247Z - 141847Z Summary...Training, organized convection continues across portions of central AL and south-central GA. Persistent training of thunderstorms with rainfall rates upwards of 2-3"/hr could yield an additional 2-4" of rainfall along a narrow axis through 19z. Discussion...Radar and IR imagery trends this morning depict an intensifying complex of thunderstorms exhibiting training over central AL into south-central GA. Multi-source hourly rainfall estimates upwards of 1.5-2"/hr were noted within the most intense convective cores, which corroborate earlier hourly rainfall estimates of 1.6-2.2"/hour from several CWOP stations south and east of Birmingham. Repeat rounds of this activity led to an elevated swath of FLASH CREST responses oriented along a Birmingham to Fort Benning Line. Meanwhile, developing shallow convection was noted south of this intense complex over southeast AL. This activity persists within an increasingly favorable environment for organized, training convection atop an east-west stationary front analyzed across the region. An approaching unseasonably strong subtropical jet has led to a focused corridor of 20-30 kts of southwesterly 850 mb inflow oriented semi-orthogonal to the surface front to support development of new cells on the south and western flank of the complex. Meanwhile, SPC mesoanalysis depicts a moisture-laden airmass across the region with 1.6-1.8" PWATs, which would hover within the 75th-90th percentile for this time of year, with warm cloud layers of 3500-4000 meters noted per the RAP. 2000-3000 J/kg of MUCAPE is also noted along the flank of the complex, with the RAP also suggesting increased surface based inflow from the southwest. Owing to the approaching unseasonably strong subtropical jet, effective shear is forecast to strengthen to 50-60 kts, which will continue to support highly convection going into this afternoon. Although CAM guidance has struggled overall with the timing and placement of the activity this morning, there is a general consensus for a focused axis of heavy rainfall across central AL into south-central GA through 19z, as reflected by the overnight HREF. In spite of high FFGs across the region (3"/hr and 3-4"/3 hr), repeat rounds of organized convection with increased rainfall rates upwards of 2-3"/hr could lead to additional rainfall totals of 2-4" to support possible flash flooding through at least 19z. A signal for additional rounds of convection past 19z will be closely monitored for additional MPD concerns. Asherman ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7gs9E8okCgyXuZ6Wo5p10qX3uEwIhUHf6xl425nUp1S2Dfwaq8KE-IJH40td95W5sCVZ= 99LIqvWnt86atIqN4rlpg5A$ for graphic product... ATTN...WFO...BMX...FFC...TAE... ATTN...RFC...SERFC...NWC... LAT...LON 33578615 33278478 32638267 31688328 31878526=20 32438656 33248722=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) .