Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jan 02 2023 19:41:55 AWUS01 KWNH 021941 FFGMPD TNZ000-KYZ000-ILZ000-MSZ000-MOZ000-ARZ000-030140- Mesoscale Precipitation Discussion 0002 NWS Weather Prediction Center College Park MD 241 PM EST Mon Jan 02 2023 Areas affected...central AR into the MS and lower OH Valleys Concerning...Heavy rainfall...Flash flooding possible Valid 021940Z - 030140Z Summary...The flash flood potential will increase from central AR into portions of the middle MS and lower OH Valleys into the early evening. Southwest to northeast training will likely support 1-2 in/hr rain rates and 2-3 inches in 3 hours through 01Z. Portions of the area have elevated soil moisture values due to recent heavy rainfall from late last week which may increase runoff potential. Discussion...Regional radar imagery at 19Z showed scattered thunderstorms extending from south-central AR into northern MS and western TN, at the leading edge of higher low level moisture transport. Station plots from 19Z showed the northern edge of near or above 70F dewpoints extended from northeastern TX into southern AR and north-central MS, more reminiscent of a mid-spring pattern. 850 mb winds along and just west of the lower MS River were 30-40 kt with 40+ kt from eastern TX into southeastern OK, supporting rapid increases in low level moisture. Precipitable water values have risen 0.2 to 0.4 inches over the past 6 hours via sounding data from SHV and LZK between 12 and 18Z, and exhibited standardized anomalies of +2 to +3 for early January. Meanwhile, MLCAPE ranged from 500-1500 J/kg from southern MO/KY into central AR via 18Z sounding and SPC mesoanalysis data. Moisture transport is forecast by recent RAP cycles to increase across the middle and lower MS Valley through 00Z, in tandem with mid-level height falls tied to an approaching closed low/trough over the central/southern Rockies. This should result in an increase in the coverage of thunderstorms over the next 6 hours with transient axes of SSW to NNE low level convergence setting south of and along the leading edge of the low level moisture transport. With unidirectional flow from the SSW, training axes of thunderstorms are likely to develop which would contain rainfall rates of 1-2 in/hr per the environment in place. Portions of AR received 2 to 4+ inches of rain from December 29-30, which has increased relative soil moisture values in the 0-40 cm layer above the 60 percent via data from NASA SPoRT. Area flash flood guidance values ranged from 2 to 3 inches in 3 hours, and the chances of surpassing these values should increase through 00Z. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-ntzJprCHjvDAFL4IdJ2Bsrep7hldKk8N0R4GxvzMCyI7_1tUMKWnt8LPZ4QsFYvI6g1= YwiWEUTJabTXvO42IWDEZFc$ for graphic product... ATTN...WFO...LZK...MEG...OHX...PAH...SGF... ATTN...RFC...ABRFC...LMRFC...OHRFC...NWC... LAT...LON 37698831 37238767 36308762 35378826 34788911=20 34309024 34119204 35019263 36199203 37168983=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) .