Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Oct 12 2023 02:41:14 AWUS01 KWNH 120241 FFGMPD FLZ000-120835- Mesoscale Precipitation Discussion 1142 NWS Weather Prediction Center College Park MD 1040 PM EDT Wed Oct 11 2023 Areas affected...Panhandle and Big Bend of FL Concerning...Heavy rainfall...Flash flooding possible Valid 120239Z - 120835Z Summary...Flash flood potential will increase across portions of the FL Panhandle and Big Bend over the next 6 hours. Areas of training with rainfall rates of 1 to 3+ in/hr will be possible with 6 hour totals of 3 to 6+ inches through 09Z. Discussion...Regional radar imagery over the past 3 hours has shown thunderstorms and showers containing heavy rain over the northern Gulf of Mexico edging closer to the FL Panhandle. Peak MRMS-derived rainfall rates have ranged between 1-3 in/hr but have been limited in northward extent due to a lack of instability. Moisture values were already high to the north of a warm front located in the northern Gulf (2.0-2.2 inch PWATs from 00Z RAOBs at LIX and TLH) but poor 700-500 mb lapse rates near 5 C/km were limiting instability. Higher moisture with tropical origins (2.5+ inches PWAT) and instability (1000+ MLCAPE) were located along and south of the warm front which has been trending closer to the coast over the past few hours. Short term guidance from the recent hi-res and global consensus supports the warm front continuing to lift north overnight as a surface low near the MS River Delta and possible convectively generated lows along the warm front edge northward over the next few hours. As the warm front lifts north across the Forgotten Coast and possibly across the Nature Coast through 09Z, low level moisture advection will support an increase in instability near/south of the warm front and rainfall rates of 1 to 3 in/hr due to training. However, the potential for rainfall rates of 3+ in/hr will exist along with the possibility for slow moving mesocyclones near the frontal boundary which could allow for rainfall rates in excess of 3 in/hr. While this potential exists, it is of a lower probability and likely to remain highly localized if it occurs. Nonetheless, repeating rounds of heavy rain with occasional high rates are likely to allow for rainfall totals to increase into the 3 to 6+ inch range through 09Z for portions of the FL Panhandle and possibly into the Big Bend region. Despite very high FFG, localized flash flooding will be possible due to the potential for increasing rainfall totals overnight, especially across any urban or low lying areas of poor drainage. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4gvT2_aq9RKKwvG4uXWDf1EblaFJRZEWzmnrlDWlSOgRz0ZTI6kHhnAiJ6yO5xuF1OPV= uRZCW2b3YEmJfGlwDpGzIhI$ for graphic product... ATTN...WFO...JAX...MOB...TAE...TBW... ATTN...RFC...SERFC...NWC... LAT...LON 30518663 30488611 30418528 30398466 30358414=20 30258372 29958316 29498284 29118278 28868268=20 28618271 28508279 28528300 28618322 28828354=20 29298387 29448436 29318489 29268512 29408557=20 29698611 29798637 29868666 29958687 30148698=20 30378689=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) .