Subj : MESO: Mesoscale Discussion 2134 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Sep 27 2025 00:35:37 ACUS11 KWNS 270035 SWOMCD SPC MCD 270035=20 AZZ000-270230- Mesoscale Discussion 2134 NWS Storm Prediction Center Norman OK 0735 PM CDT Fri Sep 26 2025 Areas affected...South-central Arizona Concerning...Severe Thunderstorm Watch 621... Valid 270035Z - 270230Z The severe weather threat for Severe Thunderstorm Watch 621 continues. SUMMARY...Isolated strong to severe thunderstorms will remain possible for the next couple of hours, but the overall severe threat is beginning to wane across south-central Arizona. DISCUSSION...Over the past 30-45 minutes, convection across south-central AZ has undergone steady weakening per MRMS metrics and cloud-top temperatures. The exception to this is a cluster across portions of northeastern Pinal county where re-development along a southward propagating outflow boundary continues to periodically intensify to severe limits per MRMS MESH and KIWA velocity data. A recent 00z sounding from TUS sampled modest mid-level lapse rates, but adequate low/mid-level moisture to support around 1000 J/kg MLCAPE when adjusted for warmer surface temperatures further north near the ongoing cluster. Despite adequate buoyancy for deep convection, surface observations show a spatially limited warm sector remains in place, largely over portions of eastern Pinal and far eastern Pima counties. With redevelopment along the outflow boundary becoming increasingly sparse and several failed attempts at deep convection noted along a weak surface trough over eastern Pima county, strong/severe thunderstorm potential appears to be waning. This trend should continue heading into the evening hours as nocturnal cooling begins to increase inhibition. Nonetheless, some localized severe hail/wind threat may linger across portions of south-central AZ for the near term given residual buoyancy and adequate deep-layer shear. ...Moore.. 09/27/2025 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!9fWwcDBgQTFTElbjHj3kQxSsixfZuZzIaQLa0rh2tEfkjAmvjAsm4j3lmHTCy_372bB-BPzfN= jvUNrdS05AAGZnVRKQ$ for graphic product... ATTN...WFO...TWC...FGZ...PSR... LAT...LON 31981156 32181165 33091163 33341154 33531133 33641103 33641067 33401043 33211035 32291038 32101052 32041072 31911132 31901146 31981156=20 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN =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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .