Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jan 02 2023 21:01:18 AWUS01 KWNH 022101 FFGMPD LAZ000-MOZ000-ARZ000-TXZ000-OKZ000-030300- Mesoscale Precipitation Discussion 0003 NWS Weather Prediction Center College Park MD 400 PM EST Mon Jan 02 2023 Areas affected...Arklatex into western AR and southern MO Concerning...Heavy rainfall...Flash flooding possible Valid 022100Z - 030300Z Summary...Training and repeating thunderstorms are expected to pose a threat for flash flooding from the Arklatex into western/central AR and possibly southern MO through 03Z. Rainfall rates of 1-2 in/hr, locally higher, can be expected. Peak 6-hr totals of 3-5 inches will be possible. Discussion...Thunderstorms were ongoing at 2030Z from eastern OK into central AR along with a secondary area noted in eastern TX, moving toward the NNE between ~40-50 kt. These storms were occurring within a region of moderately strong low level moisture transport and large scale lift out ahead of a potent closed mid-level low/trough crossing the central/southern Rockies. GPS and 18Z sounding data showed precipitable water values of 1.2 to 1.6 inches from central AR into northeastern TX and SPC mesoanalysis data from 20Z indicated MLCAPE of 1000-2000 J/kg over these same locations. Mean SSW flow has already supported areas of training with 1-2 in/hr rates, noted across western AR and just west/northwest of Little Rock via MRMS data. Areas of training within ongoing thunderstorms over western AR will continue to have the potential for generating 1-2 in/hr rates with 2+ in an hour possible on a localized basis as well. Increasing large scale ascent ahead of the middle/upper trough to the west will support an increase in low level moisture transport from eastern TX into southern AR into the evening. In addition, a 100 kt jet streak near 250 mb over the Rio Grande between DRT and LRD is forecast to edge eastward in the short term which will increase diffluence and divergence aloft across the Arklatex, possibly supporting a renewed round of convection in the 23-00Z time frame over northeastern TX. These storms would track over areas of the OK/AR border into central AR which are already experiencing areas of heavy rain. In addition, portions of southern/central AR received 3 to 5 inches of rain from December 29-30 with surrounding areas to the west and north also having higher than average soil moisture due to the recent rainfall. Given wet antecedent conditions and the forecast for heavy rain, flash flooding is considered possible through 03Z from the Arklatex into the western half of AR and possibly southern MO. Lower instability across southern MO may temper the flash flood threat prior to 03Z but flash flood guidance values are only about 2 inches in 3 hours along the MO/AR border. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4UFhcFJgjLw3sjI6P0DA2eb7XjZKpzczTGNloSaomtm5xg_-B0EJQFYKoqt9F0f96wa8= TVq9Wng_K6dGF3ah2anbYnc$ for graphic product... ATTN...WFO...FWD...LSX...LZK...MEG...PAH...SGF...SHV...TSA... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 37119155 37079042 36679045 35829158 35009221=20 33699255 32869341 32519415 32709518 33469573=20 34929546 36049428=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) .