Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Nov 05 2022 02:16:46 AWUS01 KWNH 050216 FFGMPD MSZ000-LAZ000-MOZ000-ARZ000-TXZ000-050700- Mesoscale Precipitation Discussion 1112 NWS Weather Prediction Center College Park MD 1015 PM EDT Fri Nov 04 2022 Areas affected...Arkansas...South-central MO...Northern LA... Concerning...Heavy rainfall...Flash flooding possible Valid 050215Z - 050700Z SUMMARY...Increasingly progressive QLCS with embedded short-term training elements capable of 2-2.5"/hr rates resulting in scattered possible flash flooding incidents. DISCUSSION...GOES-E WV suite depicts compact strong shortwave across western OK as base of upper-level jet is starting to lift north across E TX/OK providing a last opportunity for strengthening/maintaining stronger thunderstorms. 02z surface analysis continues to see strong pressure falls with main surface cyclone across SW MO, yet, a weak meso-low along the southward extending squall line exists across W AR. Concurrently, strengthening descending CAA across the Red River Valley is accelerating toward N LA sharpening the FGEN ascent forcing along the convective line, while increasing eastward propagation vectors/cell motions, particularly along and south of the nose of the CAA; while north across central AR, a weak inflection may aid maintenance of the meso-low on the QLCS. Regional RADAR mosaic denotes with the squall line, a few remaining strong rotating cells, particularly near the meso-low.=20 Warm sector continues to narrow though still provides ample unstable air with MLCAPES of 1000-1500 J/kg across southern AR and N LA diminishing toward 250-500 near the AR/MO border. Strong moisture flux (enhanced locally by cell rotation) and Tds in the upper 60s and 70s, and sfc-850mb PWat values of .75-.9" advected by 20kts at the surface to 50kts at 85H will continue to support supercells capable of 2-2.5"/hr rates through the next few hours. Cell motions are increasing, so rainfall totals will be reducing due to duration at any given point, but likely to result in scattered localized 1.5-2.5", isolated 3" totals especially at/near the inflection of QLCS and meso-low across central AR. While FFG values are high, ground conditions are very dry/hard and given the rate of water and reduced infiltration capability, sub-hourly FFG exceedance is possible...as supported by MRMS FLASH values over 400 cfs/smi (though caution is needed given KSRX RADAR/MRMS continues to run hot compared to local observations). North into northern AR/southern MO, limited instability should reduce updraft vigor, yet lingering rotating cells may still pose a localize flash flooding threat though that will continue to diminish north and east with time and loss of instability. South of the area of highlighted MPD area, isolated pre-frontal supercells combined with cells along advancing cold front will need to be monitored for a subsequent MPD, though best moisture flux convergence may be overwhelmed by forward (southeast propagation particularly over increasingly higher FFG values aiding to limit even most isolated flash flooding risk (with exception of urban flooding concerns). Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6VsomyJszNcOJNT1ntT2wJF4mXMGQC9wE9Pd8lEYI8nnRJbpApTNGV8IjW_aQSrkk5RV= H8VD3bl1lXIF5CX9p5bZNHg$ for graphic product... ATTN...WFO...JAN...LZK...MEG...PAH...SGF...SHV... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 37049109 36599029 35709036 33289135 32209206=20 32089409 32859429 34589347 36339292 37039226=20 =20=20=20=20=20=20=20=20=20=20=20=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) .