Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Apr 19 2025 02:23:07 AWUS01 KWNH 190223 FFGMPD ILZ000-MOZ000-ARZ000-OKZ000-KSZ000-190821- Mesoscale Precipitation Discussion 0141 NWS Weather Prediction Center College Park MD 1022 PM EDT Fri Apr 18 2025 Areas affected...eastern Oklahoma through southern/east-central Missouri Concerning...Heavy rainfall...Flash flooding possible Valid 190221Z - 190821Z Summary...Several instances of flash flooding are possible through 08Z/3am this morning as convective coverage increases along/ahead of a front through the discussion area.=20 Discussion...Over the past hour, rapid thunderstorm development has materialized both along and just northwest of a surface cold front extending from near PVJ/Pauls Valley, OK northeastward to near Joplin and Springfield, MO. The storms were located in a steep mid-level lapse rate environment, with ~7C/km H7-H5 rates and 1.25-1.4 inch PW values supporting strong, quickly evolving updrafts. The orientation of the initiating front parallel to 50+ kt mean flow aloft was allowing for this initial convection to train and produce spots of 1 inch/hr rain rates (especially in northeastern Oklahoma), supporting localized flash flood potential in the short term. With time, continued evolution of convection into combinations of lines/clusters and even supercells will allow for areas of propagation to the right of mean flow. Local rain rates of 1-1.5 inch/hr are expected, which should approach hourly FFG thresholds (in the 1.5 inch/hr range - lowest in Missouri) over time. The tendency for storms to grow upscale and propagate eastward may help to mitigate a larger-scale flash flood risk tonight, although isolated to scattered instances of runoff are still expected where convective training is more pronounced. This risk will spread northeastward into more of Missouri beginning from 03Z onward and perhaps reach portions of Saint Louis and vicinity in the 07-10Z timeframe. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6ZUX32AyGcovsmm4U9pjKN1-2GU2Gd03b-N7foR5LYecVDm7Oo_n8BqPMBEnxxOfaPgY= mB5W8M_hGJ_uLhxQOafwATg$ for graphic product... ATTN...WFO...EAX...ICT...LSX...LZK...OUN...SGF...TSA... ATTN...RFC...ABRFC...LMRFC...MBRFC...NCRFC...NWC... LAT...LON 39079119 38529009 37659028 35739330 34069712=20 34359777 35499688 36779552 38229352=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) .