Authorities are warning drivers in western Iowa to slow down after responding to numerous reports of cars sliding of the road because of black ice lingering from a major snowstorm.
The Iowa State Patrol says there are several reports of single-vehicle crashes and icy road conditions. Towing has been restricted along Interstate 29 from Missouri Valley to Sioux City.
Officials in other parts of the state say cold weather has made it difficult for workers to remove black ice. Workers in Cedar Rapids say they're putting sand down but it's still difficult to cut the ice. In Des Moines, workers say de-icing agents work best above 20 degrees.
Waterloo officials say it's going to be a lengthy process to clear some residential streets.