Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Jan 12 2024 08:50:54 AWUS01 KWNH 120850 FFGMPD TNZ000-KYZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-121450- Mesoscale Precipitation Discussion 0011 NWS Weather Prediction Center College Park MD 350 AM EST Fri Jan 12 2024 Areas affected...Portions of the Lower MS Valley and Lower OH Valley Concerning...Heavy rainfall...Flash flooding possible Valid 120850Z - 121450Z SUMMARY...Heavy showers and thunderstorms with some concerns for additional cell-training may result in pockets of flash flooding through the early morning hours. The more urbanized locations and areas that have already seen heavy rainfall overnight will be at greatest risk of seeing these concerns. DISCUSSION...The latest GOES-East WV suite shows a vigorous upper-level trough advancing east across the central and southern Plains with strong shortwave energy and a strengthening mid-level jet core rounding the base of it and aiming for the Lower MS Valley. This energy along with some subtle backing of the low-level jet in conjunction with an area of low pressure lifting northeast through the Arklatex has been allowing for the rapid development and expansion of new bands of convection across areas of northeast TX through central AR. The latest RAP trends show an axis of strong low-level moisture convergence coinciding with the corridor of cooling convective tops, and this is also where there is a moderately buoyant airmass characterized by MLCAPE values of 1000 to 1500+ J/kg. PWs continue to increase with time given the persistent and enhanced south-southwest low-level jet of 50 to 60+ kts transporting moisture out of the western Gulf of Mexico. In fact, the latest CIRA-LVT data for the SFC-850 mb layer shows LVT magnitudes approaching and exceeding 250 kg/ms/s. Deeper layer IVT values overall have risen substantially over the last 6 hours as the upstream height falls/forcing continues to encroach on the region. As strong upper-level jet dynamics and related DPVA interacts with this corridor of stronger thermodynamics and enhanced moisture transport over the next few hours, a much more organized convective threat should emerge which will include concerns for convection locally repeating/training over the same area or at least impacting areas that saw heavy rain earlier in the night. The 00Z HREF guidance overall may be a tad underdone with its QPF potential early this morning given the enhanced levels of moisture transport, increased instability and convective organization. The potential will exist for some cells to produce rainfall rates of as much as 2 inches/hour, and some additional storm totals of 3 to 4 inches cannot be ruled out where any cell-training occurs. Some pockets of flash flooding will be possible, and especially where the greater overlap of earlier rains and these additional rounds of convection occurs. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!98dqfTI-f7jH0ybCqktmP6xJtVCdu9FI1YAX0NT4f0x_v24HXeHXF346mQhxTbsnwYKq= 3FHQ-v3q4iDOHYvnV7E9rmg$ for graphic product... ATTN...WFO...ILX...IND...JAN...LMK...LSX...LZK...MEG...OHX... PAH...SGF... ATTN...RFC...ABRFC...LMRFC...NCRFC...OHRFC...NWC... LAT...LON 38628775 38418674 37758661 36668738 35398866=20 34358985 33949043 33629123 33559228 33859309=20 34649339 35579267 37159076 38208902=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) .