South Dakota Department of Transportation has closed Interstate 90 from Chamberlain to Rapid City.
DOT and Department of Public Safety officials say road conditions are deteriorating and visibility is near zero in some areas.
Blowing snow and heavy drifting make travel impossible in some areas. Several vehicles are stranded along the interstate.
Travelers are urged to visit safetravelusa.com or call 511 to check road conditions in other parts of the state.
Officials urge drivers to watch the weather and be prepared to change travel plans if necessary.