Subj : MESO: Mesoscale Discussion 0524 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Apr 15 2023 16:40:02 ACUS11 KWNS 151639 SWOMCD SPC MCD 151639=20 MOZ000-ILZ000-ARZ000-OKZ000-151915- Mesoscale Discussion 0524 NWS Storm Prediction Center Norman OK 1139 AM CDT Sat Apr 15 2023 Areas affected...portions of northern/central Arkansas...southern/central Missouri and west-central Illinois Concerning...Severe potential...Watch likely=20 Valid 151639Z - 151915Z Probability of Watch Issuance...95 percent SUMMARY...Large hail (some greater than 2 inch diameter), damaging gusts and a few tornadoes are possible this afternoon across central/northern Arkansas, southern/central Missouri and west-central Illinois. A watch will likely be needed in the next couple hours. DISCUSSION...Visible satellite imagery shows deepening cumulus ahead of the eastward-advancing cold front over the NE OK/SW MO/NW AR vicinity at midday. Temperatures have warmed into the mid/upper 70s amid upper 50s/low 60s F dewpoints. This has aided in weakening inhibition and MLCAPE increasing to around 1500-2000 J/kg amid a plume of steep midlevel lapse rates (8-8.5 C/km). Increasing large-scale ascent and frontal convergence will likely support initial thunderstorm development within the area by 19z. Downstream from this destabilizing airmass toward central MO and west-central IL, stronger inhibition remains. This is partly due to elevated morning convection. However, clearing behind morning convection will allow for continued heating and airmass recovery ahead of developing convection over western portions of the discussion area.=20 Supercell vertical wind profiles will favor initial semi-discrete activity. Very steep lapse rates, large instability and elongated hodographs suggest very large hail will be possible with this initial activity. Steep low-level lapse rates and modest low-level shear also will support damaging gusts. With time and eastward extent, convection may become more of a mixed mode of semi-discrete supercells and clusters/lines as upscale development into a QLCS appears likely. Low-level shear is expected to remain modest, but small and favorably curved low-level hodographs could support some risk for a few tornadoes, especially south of the I-44 corridor in MO into north-central AR. A watch will likely be needed in the next couple of hours. ...Leitman/Grams.. 04/15/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!89FiT1sY6L5VGzUqZEy-PcrvGpRQ34Q8A9AkW8CHIg-u8z81O0-NHsTV-b4U9ME-mKHrdhaEc= 2VV7ygk7Y76qKX-cBE$ for graphic product... ATTN...WFO...PAH...ILX...MEG...LSX...LZK...SGF...EAX...TSA... LAT...LON 35109137 34839187 34719239 34659310 34879398 35179435 35969467 36619466 36869463 37439451 38179381 39239229 39609131 39679081 39619017 39288981 38878972 38378972 37938981 35929071 35109137=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) .