Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue May 09 2023 19:46:21 AWUS01 KWNH 091946 FFGMPD MOZ000-OKZ000-KSZ000-100045- Mesoscale Precipitation Discussion 0247 NWS Weather Prediction Center College Park MD 345 PM EDT Tue May 09 2023 Areas affected...Eastern Kansas...Southwest Missouri... Concerning...Heavy rainfall...Flash flooding possible Valid 091945Z - 100045Z SUMMARY...Intense sub-hourly rainfall rates/totals associated with mature MCS. Best potential for increased duration/totals (2"+ in 30 minutes) near MCV and areas affected by pre-cursory cells/lowered FFG. DISCUSSION...GOES-E Visible and regional RADAR mosaic depict a mature MCS/severe bow echo across east-central KS sliding rapidly SE along a well defined stationary front extending southeast into SW MO near SGF. Impressive streamers along the southern flank denote the strong low level response advecting moist and quite unstable air into the complex with surface Tds in the mid to upper 60s on 15-25kt sfc to 850mb accelerating flow. Combined with outflow over 50-60mph, moisture flux convergence is extreme, while deep layer moisture is limited to about 1.25-1.33" of total PWats, the isallobaric response and higher advection of 70+ Tds from E Ok will allow for increasing moisture values supporting increasingly efficient rainfall production. WoFS member 5-minute totals over ..5-.75" and HRRR 15 minute rainfall totals of 1.5"+ may become increasingly effective even though duration of rates is limited in the short-term. Expanding moderate post-squall precipitation shield as well as maturing cyclonic and anti-cyclonic rotors near the MCV and the western portions of the flanking line should allow for increased duration of intense rates as well. As such, the WoFS 50th percentiles have been steadily increasing to 2-2.5" across E central KS with 90th percentile as high as 5" for the cyclonic rotor as it slides southeastward along the stationary front. Confluent flow on both sides of the frontal boundary is also expected to increase to further enhance rainfall efficiency with time. This also may run very close to recently saturated grounds from earlier convection from Coffey, KS to Vernon, MO counties where FFG has lowered below 1-1.5" making flash flooding much more likely across this area. Sufficient convergence along the stationary front has sparked a few additional thunderstorms which may increase from widely scattered to scattered along the axis. This poses those worse case scenario presented in the 90th percentile of the WoFS at or around 5" where the squall line merges/absorbs the pre-cursory cells or slows their forward progression. So while this is less probable, it is not impossible given the trends noted in visible imagery over the last hour or so along with the WoFS/HRRR output.=20 Still confidence is not sufficient to support flash flooding being considered likely and remains possible over the next 4-5 hours. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4JovRmMM-SB4xqk4hX94oApch5tlMX5Ytx94iNW1n2DI-xMiWbj35g1m5erC6raizXQN= L2jUSblANwiiANaOucOn0tg$ for graphic product... ATTN...WFO...DDC...EAX...ICT...SGF...TOP...TSA... ATTN...RFC...ABRFC...LMRFC...MBRFC...NWC... LAT...LON 39539655 38939489 38189320 37219254 36589319=20 36759423 37349617 37649709 38009822 38439912=20 38839888 39049760 39449711=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) .