Subj : MESO: Mesoscale Discussion 2015 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Aug 18 2023 22:38:55 ACUS11 KWNS 182238 SWOMCD SPC MCD 182238=20 AZZ000-190115- Mesoscale Discussion 2015 NWS Storm Prediction Center Norman OK 0538 PM CDT Fri Aug 18 2023 Areas affected...Parts of south-central Arizona Concerning...Severe potential...Watch unlikely=20 Valid 182238Z - 190115Z Probability of Watch Issuance...5 percent SUMMARY...Sporadic strong to severe gusts could accompany any stronger thunderstorms that develop into the evening. A watch is not expected. DISCUSSION...Widely scattered high-based thunderstorms are evolving westward over parts of southeastern AZ this afternoon, with some recent evidence of locally congealing cold pools. Additional thunderstorms are spreading northward across the International border in southwestern AZ. Subtle backing of 15-20 kt midlevel flow (per regional VWP data) will allow this activity to continue spreading/developing west-northwestward through the afternoon across parts of south-central AZ. The pre-convective environment is characterized by a hot/deeply mixed boundary layer (and related steep low-level lapse rates) beneath a plume of rich midlevel moisture (PW near 1.6 inches per GOES-16 and the latest PHX ACARS soundings). While modest deep-layer shear (around 20-kt 0-6 km shear per VWP data) will generally limit updraft longevity and organization, the deep inverted-V thermodynamic profile will support strong to locally severe gusts with the stronger storms that develop into the evening -- especially with any localized clusters that evolve. Overall, the severe threat appears too sporadic for a watch. ...Weinman/Bunting.. 08/18/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-EOooIMtPHB2tnaMrZo4swHFA1pV8SC9uju5McXiA0KFZTrCZ3vS_ZTGso_tRfjaD1rDuGKGt= nvolXxMZbo3QaV7bAI$ for graphic product... ATTN...WFO...TWC...FGZ...PSR... LAT...LON 31621015 31291031 31271115 31631226 31951334 32271336 32751315 33451272 33871239 34061199 33971114 33581041 32411003 31621015=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) .