Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Aug 05 2025 19:55:17 ACUS01 KWNS 051955 SWODY1 SPC AC 051954 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Aug 05 2025 Valid 052000Z - 061200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE DAKOTAS... ....SUMMARY... Scattered severe thunderstorms with an accompanying risk for large hail, severe wind gusts, and perhaps a couple of tornadoes will be possible this afternoon through much of the evening across the Dakotas. ....20z Update... No changes were made to the D1 Convective Outlook. Air mass recovery trends continue to be monitored across the Dakotas in the wake of morning convection. Breaks in the cloud cover have led to heating across central/western South Dakota to the southern North Dakota line. Warm moist air continues to spread northward south of the differential heating boundary located across southern ND into central SD. It appears that redevelopment/re-intensification of thunderstorm activity is likely through the afternoon as further destabilization continues. See MCD#1890 for more detailed information on expected storm evolution through the afternoon. ...Thornton.. 08/05/2025 ..PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Aug 05 2025/ ....Northern Plains... Visible-satellite/radar mosaic imagery late this morning shows a cluster of sub-severe thunderstorms associated with a lead lobe of mid-level ascent/MCV moving through the base of a larger-scale trough centered over MT/Saskatchewan. Deleterious effects of widespread cloud cover over far northern SD into ND will likely hinder appreciable destabilization through the early afternoon. However, earlier forecast thinking of a differential heating zone becoming more focused along the ND-SD border to the east of a weak cyclone will potentially become consequential for the severe risk later this afternoon/evening. A reservoir of adequately rich low-level moisture with dewpoints in the mid-upper 60s deg F will likely protrude northward into southern ND as the airmass destabilizes this afternoon. Cloud breaks will contribute to moderate to strong buoyancy (1500-3500 J/kg MLCAPE) to the south of more stable conditions likely being maintained throughout the day near the Canadian border. Forecast soundings show enlarged low-level hodographs by mid-late afternoon and into the evening with a 40-kt southerly LLJ centered on SD. Short-term model guidance indicates renewed storm development is most likely east of the low along the differential heating zone with this activity spreading east into more vorticity-rich air. Seasonably large uncertainty remains regarding this forecast during the 22-02z period in which peak severe may occur. Supercells capable of all hazards will be possible before clusters evolve and the propensity for cold pool coalescence becomes detrimental for the supercell threat and wind becomes the primary hazard later this evening. Considerable uncertainty exists overnight on the potential evolution of a cluster and an incipient wind threat into parts of the MO Valley and Upper Midwest. $$ = = = 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) .