Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Aug 22 2024 09:52:17 AWUS01 KWNH 220952 FFGMPD FLZ000-GAZ000-221500- Mesoscale Precipitation Discussion 0918 NWS Weather Prediction Center College Park MD 551 AM EDT Thu Aug 22 2024 Areas affected...southeastern GA into northeastern FL Concerning...Heavy rainfall...Flash flooding possible Valid 220950Z - 221500Z SUMMARY...Slow moving showers/thunderstorms, capable of localized rainfall rates over 3 in/hr will likely continue for another few hours in the vicinity of the GA/FL border near the coast. Localized flash flooding will be possible, especially with any overlap of urban areas. DISCUSSION...0930Z radar imagery from KJAX showed a small region of slow moving showers and thunderstorms located between I-95 and the coast in Camden and Nassau counties (southern GA/northern FL). Local Wunderground.com reporting stations showed agreement with KJAX rainfall estimates showing hourly rainfall of 2 to 3 inches associated with cells observed on radar. This region was located just north of a stationary front with 0-1 km AGL flow from the east between 10-20 kt, advecting warm moist air in from the Atlantic. SPC mesoanalysis data from 09Z showed SBCAPE over 2000 J/kg just offshore and a narrow axis of weaker but sufficient and uninhibited instability inland, straddling the GA/FL border. Area surface observations showed a convergence axis located near or just east of I-95, coincident with the ongoing slow moving showers/thunderstorms. There is little change to the overall setup expected over the next 3 to 6 hours, although the onset of daytime heating after sunrise may disrupt the existing gradient/convergence axis in place. Nonetheless, some degree of frictional convergence with continued low level onshore flow within the instability axis is expected to continue a threat for slow moving showers and thunderstorms in the vicinity of the GA/FL border. There is some concern for the ongoing activity to build south toward the Jacksonville metro region which would have greater sensitivity to flash flood impacts due to the urban nature compared to surrounding, more rural area. Within the slow moving areas of heavy rain, hourly rainfall of 2-3 inches is expected but values could surpass 3 inches in an hour in the more persistent activity with 6-hr rainfall totals possibly exceeding 6 inches in some locations. Flash flooding will be possible as a result. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!__A1yL7rYBfSFbtad1hReY1e8HMh0OVl6pACO9lUr5zi9vRKh_qxymTzo2zCSUdE42o0= hYvX-uScDijBIne17mL_pL0$ for graphic product... ATTN...WFO...CHS...JAX... ATTN...RFC...SERFC...NWC... LAT...LON 31458177 31308115 30838124 29898118 29728169=20 29918219 30348235 30918221=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) .