At 847 PM CDT, a severe thunderstorm capable of producing a tornado was located over St. Helena, or 9 miles southeast of Yankton, moving east at 40 mph.
HAZARD...Tornado and ping pong ball size hail.
SOURCE...Radar indicated rotation.
IMPACT...Flying debris will be dangerous to those caught without shelter. Mobile homes will be damaged or destroyed. Damage to roofs, windows, and vehicles will occur. Tree damage is likely.
This tornadic thunderstorm will remain over mainly rural areas of northeastern Cedar County, including the following locations... Menominee, Brooky Bottom, and St. Helena Boat Dock.