Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Aug 13 2024 11:23:20 AWUS01 KWNH 131123 FFGMPD MOZ000-ARZ000-OKZ000-KSZ000-131700- Mesoscale Precipitation Discussion 0874 NWS Weather Prediction Center College Park MD 722 AM EDT Tue Aug 13 2024 Areas affected...Southeast KS...Southwest MO...Northeast OK...Northwest AR... Concerning...Heavy rainfall...Flash flooding possible Valid 131130Z - 131700Z SUMMARY...Decaying MCS with a few more hours of WAA training along the northern side of strengthening bow echo allowing for 2-4" totals and possible flash flooding. Very intense short-term rates with 1-2" in 15-30 minutes with the bow may be a flooding concern in prone or urban settings. DISCUSSION...Regional RADAR mosaic depicts a well defined MCV/parent shortwave that has become well displaced in the decaying shield precipitation WNW of the strengthening effective triple point/new MCV near Marion/Chase county, KS. A impressive bowing segment is surging ESE into SE KS, with a broadening upstream edge across south-central KS within the MCS anti-cyclonic rotor. While strong moisture flux convergence will quickly turn with very short-duration resulting in 1-2" of rainfall in 15-30 minutes likely only resulting in flooding in traditionally prone or urban settings.=20 Of greater potential for flash flooding are within the bookends of the MCS; the upwind southern anti-cyclonic rotor is starting to have broadening convective elements being more exposed to the southwesterly LLJ and expanding moisture convergence orthogonal to the mean motions as the MCS enters a bit more NW to SE motions in the 500-1000 thickness pattern (directing toward SW MO/NE OK). VWP shows increasingly unidirectional inflow still at 25-35kts from 925-700mb advecting an axis of enhanced conditionally unstable air with MUCAPE of 1500-2000 J/kg across north-central OK. This may result in an area of enhanced 2-3" totals into the southern Flint Hills and perhaps northern Osage county. The other location remains with the stronger WAA along/ahead of the MCV on the cyclonic rotor; here, strengthened flow and directional convergence results in the greatest moisture flux to the system and should support 2-2.5"/hr rates particularly near the transferred MCV. However, recent trends show a shortening of the downstream convergence and convective development. There may be two factors involved, the first: utilizing EAX VWP, downstream winds are weaker at less than 10kts with even some lesser than desirable southerly component. The second is related to a reduced instability pool downstream into MO. RAP analysis suggests values of 500-1000 J/kg exist, but strengthening CINH fields in combination with weakening isentropic ascent on the effective warm front may reduce the length of the WAA wing and therefore training/repeating potential as the wave passes. Still, the risk of 2-4" totals in 2-3hrs will continue to pose a flash flooding risk as the MCS slowly decays through the remainder of the morning.=20=20=20 Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9Mi-JRkR1RgyQ64aAyaldVhEqm4_28eKSGKAiDFz26cMuHXkn5Gl1ps7QcWHB3RQQFwU= fhRjn9AanXTFC56dKB3UPTc$ for graphic product... ATTN...WFO...EAX...ICT...LZK...OUN...SGF...TOP...TSA... ATTN...RFC...ABRFC...LMRFC...MBRFC...NWC... LAT...LON 38809660 38669435 37999226 36829149 36139183=20 35689270 35689382 35919492 36459618 37199736=20 38289764=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .