Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Nov 13 2024 22:02:34 AWUS01 KWNH 132202 FFGMPD TNZ000-KYZ000-INZ000-ALZ000-ILZ000-MSZ000-140400- Mesoscale Precipitation Discussion 1155 NWS Weather Prediction Center College Park MD 501 PM EST Wed Nov 13 2024 Areas affected...MS River Valley into northern MS, western TN/KY, southwestern IN Concerning...Heavy rainfall...Flash flooding possible Valid 132200Z - 140400Z SUMMARY...Training thunderstorms across the lower MS/OH Valleys will be capable of 1 to 2+ in/hr rainfall rates and localized totals up to 3 inches through 04Z. Isolated flash flooding may occur as a result. DISCUSSION...Infrared satellite and radar imagery showed scattered showers and thunderstorms across the lower OH and MS Valleys into portions of central MS/western AL as of 2130Z. Forcing for ascent included lift ahead of a mid-upper level trough moving east through the central/southern Plains, with cells near and east of a low level (925-850 mb) confluence axis located across the lower MS Valley, which also extended northward into the lower OH Valley although not as strongly when compared to locations farther south. Low level warm advection was also contributing to heavier rainfall across the IN/KY border, located at the leading edge of 50-60 kt 850 mb winds via VAD wind and short term RAP forecast data. Instability was somewhat limited however, with 500 to 1000 J/kg MLCAPE confined to central MS and elevated CAPE in excess of 500 J/kg in pockets farther north into western KY via 21Z SPC mesoanalysis data. Water vapor imagery showed the mid to upper level trough over the central Plains acquiring a negative tilt which wil continue east into the overnight. Out ahead, diffluent flow across the lower OH Valley will aid in ascent with the slow eastward moving axis of low level confluence likely allowing for repeating/training rounds of heavy rain which could allow rates to reach into the 1-2 in/hr range through early overnight. To the south, across central/northern MS into western TN, locally higher instability should support greater intensity rainfall with ascent aided within the right entrance region of a 100-110 kt upper jet max located east of the advancing upper trough. The axis of low level confluence located in MS/western TN is expected to translate slowly but steadily toward the east over the next few hours which should limit training potential, however, periods of short-term training will still be possible, including the potential for more organized cells due to the combination of greater instability and favorable shear profiles. Rainfall rates of 1 to 2+ in/hr cannot be ruled out along with isolated areas of flash flooding through 04Z. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7OHFwLbNh11sOpNmvwiFeD7aeQcr4aO1WoVQgLU7WPVyU2fYz_h7LYtEB3Ox3Uk0p2DJ= SxMwR_xY7W8XO8rqLXmkJxM$ for graphic product... ATTN...WFO...BMX...HUN...IND...JAN...LMK...MEG...OHX...PAH... ATTN...RFC...LMRFC...OHRFC...SERFC...NWC... LAT...LON 38778598 38258572 37498613 35788696 34348750=20 32798866 32829016 33219054 34799016 36148939=20 37438836 38618692=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) .