Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Aug 04 2025 18:34:42 AWUS01 KWNH 041834 FFGMPD FLZ000-GAZ000-050030- Mesoscale Precipitation Discussion 0865 NWS Weather Prediction Center College Park MD 233 PM EDT Mon Aug 04 2025 Areas affected...Northeast FL...Eastern GA Concerning...Heavy rainfall...Flash flooding possible Valid 041833Z - 050030Z SUMMARY...Very heavy showers and thunderstorms will be developing and expanding in coverage over the next few hours. High rainfall rates and rather slow cell-motions will favor some potential for at least isolated areas of flash flooding, including some urban flooding concerns. DISCUSSION...The mid-afternoon GOES-E GeoColor satellite imagery shows an increasingly expansive and agitated CU/TCU field across northeast FL and into adjacent areas of eastern GA where solar insolation has been rather strong over the least several hours. This has led to MLCAPE values increasingly to 2000 to 3000 J/kg which is also being aided by very high surface dew points running generally in the upper 70s to near 80 degrees. A quasi-stationary front draped west to east across the region is favoring a corridor of stronger low-level convergence which coupled with the strongly favorable thermodynamic environment is expected to allow for locally very heavy shower and thunderstorm activity to initiate and expand in coverage over the next few hours. The 12Z HREF guidance shows high probabilities (50 to 70 percent) of seeing 2+ inch/hour rainfall rates with the convection this afternoon across areas of northeast FL and into southeast GA. These heavier rates will be near some highly urbanized areas (including the Jacksonville metropolitan area), and this may result in some urban flooding impacts. Recent rainfall extending up into adjacent areas of eastern GA have at least moistened the soil conditions a bit, and the proximity of the front along with diurnally-enhanced instability will favor a new threat of heavy rainfall extending north across much of eastern GA going into the early evening hours. The recent HRRR guidance and the 12Z HREF suite support some rainfall totals by this evening of 2 to 4 inches, with a spotty instance of 5 inches possible where some of these slower cell-motions and potential for cell-mergers occur. A few isolated areas of flash flooding will be possible given the setup and this will include the aforementioned concerns for some urban flooding. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6kEwdXGS-yQc4eRN3tyaMrV-zmU6EbHElodZUeizDreCd5MxWSKimmFlB5jmsNl-fKCl= E0X767pjqFPC6SxFs0VD7oc$ for graphic product... ATTN...WFO...CHS...FFC...JAX...MLB...TAE... ATTN...RFC...ALR...NWC... LAT...LON 32448236 32208148 31808113 30598133 29148085=20 28778106 28968157 29828198 30728280 31268356=20 32198318=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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .