Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Apr 19 2025 11:37:58 AWUS01 KWNH 191137 FFGMPD MOZ000-ARZ000-OKZ000-191700- Mesoscale Precipitation Discussion 0144 NWS Weather Prediction Center College Park MD 737 AM EDT Sat Apr 19 2025 Areas affected...Northwest AR...Southwest MO....Far Eastern OK.... Concerning...Heavy rainfall...Flash flooding likely Valid 191135Z - 191700Z SUMMARY...Another round of strong thunderstorms crossing recently saturated/flooded grounds increasing the potential for flash flooding through early morning. DISCUSSION...10z Surface analysis depicts a complex analysis with old outflow boundaries/mixed air with exiting meso-high across MO into NE OK. To add to the complexity, a sharpening upper-level right jet entrance region is lifting north across central OK into E OK/W KS resulting in falling pressures downstream across SW MO backing low level flow and increasing deep layer moisture flux convergence. This shortwave DPVA/Upper-level divergence ascent pattern is noted well in the GOES-E WV suite, with numerous overshooting cooling tops breaking through the cirrus canopy across E OK starting to encroach on SW MO/NW AR. CIRA LPW backed up by RAP analysis denotes a slug of enhanced deep layer moisture up to 1.75", along and downstream of the shortwave to increasing rainfall production/efficiency over the next few hours. Early morning convection limiting factor is typically lack of instability; however, a well of mid 70s Temps over mid to upper 60s Tds and solid lapse rates does support along stream instability with SBACAPEs of 1000-1500 J/kg from SE OK to W-central AR, likely to be advected northward across the old outflow boundary/cold front. The source is not very large and may limit coverage and/or duration of convective activity but should be sufficient to support 1.5-2"/hr rates. The growing concern is the overlap/intersection with already saturated/flooded ground conditions across NW AR and so potential of an additional 2-3" (mainly in less than 1-1.5hrs) will likely result in flash flooding conditions in a few spots, but the expansion of the area/source of instability will allow for southward and eastward propagation an may expand the areal coverage for flash flooding over the coming hours. Further diurnal stabilization toward late morning will likely reduce intensity with loss/usage of remaining unstable air and coverage/intensity should decrease toward 16-17z and into south-central MO/northeast AR. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5wjEgPOcun6IIk5wKgeLwfqk7XzBAg9KVnLkwOe46TajoRX8scNBdzJ3MuyiN9u3qteg= 7faW3qEvrHpzFTMtHtikkuY$ for graphic product... ATTN...WFO...LZK...SGF...TSA... ATTN...RFC...ABRFC...LMRFC...MBRFC...NWC... LAT...LON 37189238 37069184 36809132 36249113 35729134=20 35189203 34799318 34609408 34529487 34579543=20 34979555 35969508 36699454 37099363=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) .