Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Oct 24 2023 21:52:57 AWUS01 KWNH 242152 FFGMPD MOZ000-OKZ000-KSZ000-250345- Mesoscale Precipitation Discussion 1151 NWS Weather Prediction Center College Park MD 552 PM EDT Tue Oct 24 2023 Areas affected...northern OK into eastern KS and northwestern MO Concerning...Heavy rainfall...Flash flooding possible Valid 242145Z - 250345Z Summary...Southwest to northeast training of heavy rain may support isolated flash flooding with 1-2 in/hr rainfall rates and 2 to 3 hour totals of 3-4 inches from northern OK into eastern KS and northwestern MO through 03Z. However, dry antecedent conditions across many areas should keep flash flood coverage on the low side. Discussion...Regional radar imagery through 21Z helped identify a few low level vorticity centers from northern OK into eastern KS, just ahead of a larger scale mid-level trough axis extending from south-central KS into northwestern TX on water vapor imagery. An axis of low level convergence was noted from northern OK into eastern KS, located at the leading edge of southerly 40-50 kt 825-850 mb flow. While instability has been weak along the KS/OK border, the advection of low level moisture from the south has supported a 100-400 J/kg increase in MLCAPE over the past 3 hours in northern OK, per 21Z SPC mesoanalysis data, resulting in 250-1000 J/kg over central OK, highest over southern locations. Ending at 21Z, 2 to 3 hour rainfall totals across Ponca City were in the 3-4 inch range, with total rainfall since 12Z just over 5 inches via a couple of Wunderground stations. Short term forecasts from the RAP showed that instability will continue to increase through 03Z, with increases in MLCAPE to near 250 J/kg along the KS/MO border and near 1000 J/kg over northern OK. As the low level vorticity maxima continue to translate northeastward, an axis of low level convergence will focus from northern OK into eastern KS with little movement over the next few hours. Given steering flow oriented parallel to the convergence axis, training will be a concern at times with rainfall rates peaking in the 1-2 in/hr range. While these rates are below flash flood guidance fFFG) values, if an area of training is able to maintain over a given location for 2+ hours, exceedance of FFG could occur. Aiding lift across the region will be modest diffluence aloft and divergence within the right-entrance region of a strengthening/broadening 120 kt jet near 200 mb over the north-central Great Plains. With the exception of heavy rain which impacted north-central OK over the past 6 hours, the region has been in a long term drought which should limit the coverage of any areas of flash flooding to isolated regions. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5cabAxHqgT5TaurQkmTcpdgvhWM_XQjWFz5-YGZ_EFGyRx3nlA-iRAbf1sOzD262OPOL= hnRTNQ3f1nnAXxGBMcs4K_w$ for graphic product... ATTN...WFO...EAX...ICT...OUN...SGF...TOP...TSA... ATTN...RFC...ABRFC...MBRFC...NWC... LAT...LON 39749459 39169380 37559493 35969752 36729841=20 38459688=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) .