The storm could produce gusty winds -- there's a 2% chance of tornadoes in the Casper-area. Severe hail will be the size of a quarter or bigger in Central Wyoming.
A supercell thunderstorm dropped hail larger than softballs in southern Sioux County, Nebraska Tuesday evening, according to the National Weather Service in Cheyenne.
The Cheyenne Office of the National Weather Service says hail and strong winds are possible this afternoon [May 17] in southeast Wyoming and the Nebraska Panhandle.