Winter storm warnings are in effect for parts of Colorado and Wyoming into Monday, as a spring snowstorm blankets the region. People in Southern Nebraska are dealing with damage from several tornadoes. (May 12)
Video provided by AP

Dozens of snowplows took to the streets of Denver early Monday, after a powerful spring storm made a wet, cold mess of Mother’s Day in parts of Colorado and Wyoming, while powerful thunderstorms moving through Nebraska produced damaging tornadoes.

More than a foot of snow fell on parts of Colorado and Wyoming. The National Weather Service issued a winter storm warning for most of northern Colorado and parts of southern Wyoming for all of Sunday and for Monday morning.

A tornado touched down at Sutton, Neb., and photos posted on Twitter showed damage to building exteriors. There were sightings of twisters in other parts of eastern Nebraska, the Weather Channel reported.

Tornado watches were out for parts of Iowa, Nebraska and Oklahoma. At least one twister touched down in Lee County in southwestern Iowa.

The National Weather service said big hail could fall in central and northern Kansas through southeast Nebraska. Thunderstorms were forecast from San Antonio to Chicago.

Accumulations could reach up to 15 inches of snow over part of Colorado and Wyoming, with enough force to cause power outages and treacherous driving conditions. Denver officials said they were deploying 70 snowplows overnight to prepare for Monday’s commute. At 3 a.m. Monday, the weather service said it was still snowing around the city.

Wintry conditions forced the closure of a 150-mile stretch of Interstate 80 between Cheyenne and…