A tornado warning is in effect for an area north of Casper.
The National Weather Service says a severe thunderstorm capable of producing a tornado was located near Antelope Hills, 14 miles north of Casper, at 5:35 p.m.
Potential hazards include a tornado and quarter-size hail. Radar indicated rotation.
The warning includes I-25 between mile markers 195 and 209. It is in effect until 6 p.m.
Area residents are urged to take cover now.