Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Aug 24 2024 19:27:16 ACUS03 KWNS 241927 SWODY3 SPC AC 241926 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 PM CDT Sat Aug 24 2024 Valid 261200Z - 271200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA AND FAR NORTHERN NEBRASKA INTO PARTS OF MINNESOTA AND WISCONSIN... ....SUMMARY... Severe storms are expected to evolve within a zone extending from the northern High Plains eastward to the Wisconsin vicinity during the afternoon and evening Monday. A few severe storms are also expected across the Northeast and Mid-Atlantic region. ....Northern Plains/Upper Midwest... An upper trough will develop east across the northern Plains on Tuesday. Enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread a very moist boundary layer (dewpoints in the 70s). A surface cold front will be oriented from northern MN southwest into western SD during the morning, and develop southeast through the period. Convection will develop along the boundary during the day and move across a strongly unstable airmass. Clusters may develop into a fast-moving MCS impacting portions of eastern SD into central/southern MN and parts of WI. Damaging wind swaths and isolated large hail will be possible. The south and east extent of the severe risk is uncertain, and adjustments may be needed in subsequent outlooks as mesoscale details become better resolved. Additional more isolated strong to severe storm may develop in the post-frontal upslope flow regime across NE and parts of the northern High Plains. Strong gusts and hail could accompany this activity. ....Northeast/Mid-Atlantic vicinity... Moderate northwesterly deep-layer flow will persist over the region as an upper trough shifts east over the Atlantic. A seasonally moist airmass will result in pockets of weak instability, supporting isolated to scattered corridors of thunderstorm activity. Steep low-level lapse rates and sufficient vertical shear amid weak instability will support isolated strong gusts and perhaps small hail. ....Central/Southern High Plains vicinity... Severe probabilities have been removed from this area with this update cycle. Forecast guidance varies considerable regarding the degree of destabilization across the region, with ECMWF members showing very little instability, while the more aggressive NAM solutions indicated MUCAPE to near 500 J/kg. Given potential for a large area with little risk, opted to remove this area until confidence increases in which particular areas may see greater thunderstorm coverage. ...Leitman.. 08/24/2024 $$ = = = 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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .