Thunderstorm Wind in Lincoln County, South Dakota

Most of the rubber roof liner on the section of Lennox High School with the band and shop classrooms was removed by thunderstorm winds. Interior ceilings and equipment incurred water damage. Property damage costs are a rough estimate.

An unstable warm sector with MUCAPE up to 2000-2500 J/kg developed during the afternoon between an advancing cold front across southeast South Dakota and a gangly warm front extending into southwest Minnesota. An approaching weak impulse spurred rapid development of multiple rounds of storms near the warm front, initially discrete, with upscale growth into short bowing segments. Secondary development occurred during the evening along the cold front, which evolved into a slow-moving linear system with hail, wind, and heavy rainfall with shear vectors increasingly parallel to the boundary.