Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Sep 20 2023 00:54:07 AWUS01 KWNH 200054 FFGMPD MOZ000-ARZ000-OKZ000-KSZ000-200650- Mesoscale Precipitation Discussion 1085 NWS Weather Prediction Center College Park MD 853 PM EDT Tue Sep 19 2023 Areas affected...nern OK, sern KS into swrn MO, nwrn AR Concerning...Heavy rainfall...Flash flooding possible Valid 200050Z - 200650Z Summary...The threat for flash flooding will increase across northeastern OK/southeastern KS into southwestern MO and northwestern AR through 07Z. Rainfall rates of 1-2 in/hr are expected to develop from training and backbuilding of storms overnight. Localized storm totals over 3 inches will be possible. Discussion...Regional radar imagery at 00Z showed a few showers/thunderstorms extending from southeastern KS into northwestern AR, located ahead of a mid-level vorticity max in southeastern KS. These storms were elevated, located north of a warm front analyzed from southwestern KS into northeastern TX. Precipitable water values in central OK into southwestern MO ranged from 1.3 to 1.6 inches (recent GPS data and 00Z SGF RAOB) with estimated MUCAPE of ~500 to 2000 J/kg...highest toward the southwest (SPC mesoanalysis). Aloft, an upper level jet max of 100 to 110+ kt was located from near ABQ to the Red River, placing eastern OK within the divergent left exit region, where flow was also diffluent ahead of an upper trough axis located over central KS. Forecasts from the RAP indicate the low level jet will increase to near 45 kt over central OK by 06Z, supporting increasing isentropic ascent and cell coverage north of the warm front. The increased overrunning of the surface boundary is expected to focus the development of convection near/north of the 925 mb reflection of the warm front, beneath divergent/diffluent flow aloft. The orientation of the elevated frontal boundary and steering flow will be similar, allowing for the potential for training and repeating rounds of cells. There will also be the potential for slow moving cells farther north into KS/MO where 850-300 mb layer mean wind speeds will be less than 10 kt near the slow moving vorticity max. While soils are dry from a lack of rain in recent weeks and flash flood guidance is correspondingly high (3+ inches in 3 hours), an isolated threat for flash flood will still exist, though it may be limited to urban areas and other locations of poor drainage. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7E4LxuR8Hocs0TY0xcg5ytgI1SrCj7mJs-cHoaJKg8SjotHPurbnhtQAGq9IPwghlV4b= 3kfkFZ2548Nx1jLBpq6zfR4$ for graphic product... ATTN...WFO...ICT...LZK...OUN...SGF...TSA... ATTN...RFC...ABRFC...LMRFC...MBRFC...NWC... LAT...LON 38029445 37949396 37569349 37249335 36689322=20 36369328 35889343 35399376 35119422 35129551=20 35429733 36299784 36829730 37089688 37509624=20 37889543=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) .