Subj : MESO: Mesoscale Discussion 1524 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jul 13 2023 19:23:31 ACUS11 KWNS 131923 SWOMCD SPC MCD 131923=20 NEZ000-SDZ000-COZ000-WYZ000-132130- Mesoscale Discussion 1524 NWS Storm Prediction Center Norman OK 0223 PM CDT Thu Jul 13 2023 Areas affected...Eastern WY...southwestern SD...western NE...and far northeastern CO Concerning...Severe potential...Watch likely=20 Valid 131923Z - 132130Z Probability of Watch Issuance...80 percent SUMMARY...The severe-storm risk will likely increase during the next couple of hours, with very large hail and damaging winds possible. A watch issuance is likely for parts of the area this afternoon. DISCUSSION...Latest day cloud phase satellite imagery indicates increasingly agitated boundary-layer cumulus along the higher terrain in eastern WY into northern CO, and additional deepening over the Black Hills in western SD. Continued diurnal heating and related orographic ascent should support isolated to widely scattered thunderstorm development during the next couple of hours. As storms intercept increasing boundary-layer moisture (lower/middle 60s dewpoints) beneath steep midlevel lapse rates in the lee of the higher terrain in WY/CO, updrafts should intensify and increase in coverage amid east-southeasterly upslope flow. Weaker instability farther north into the Black Hills casts uncertainty on updraft intensity, though a couple strong storms cannot be ruled out. 40-50 kt of effective shear and generally weak large-scale ascent should favor discrete/semi-discrete supercells initially, with a risk of very large hail and severe gusts. With time, cell-mergers could yield a couple organized east-southeastward-moving clusters with a continued hail risk and increasing damaging-wind potential. A watch will likely be needed for parts of the area this afternoon. ...Weinman/Bunting.. 07/13/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!6POVooN9uB_e-ja7mNpDBWKVzpRMQrWguCl43cLIfmuZZOJ5K1soFbE-H1sxfaNDVzXN9YrcC= 5DPSn8Hy0hud5uERaQ$ for graphic product... ATTN...WFO...LBF...UNR...BOU...CYS... LAT...LON 40610217 40380299 40100346 39830396 39850450 40070471 40400476 41990487 43050490 43930483 44240450 44420396 44450343 44290261 43990208 43440160 42520154 41410157 40610217=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) .