A slow-moving storm that slammed into the Rockies late this week is now blamed for contributing to a chain-reaction crash on a wet stretch of I-70 near Denver Friday.

Colorado State Police tell KDVR , including another tour bus, near the intersection of I-70 and E-470.

The Associated Press said a dozen people were hurt; at least one person was seriously injured.

Part of a tour bus involved in an accident with a tractor trailer sits in a westbound lane of Interstate 70 Friday, April 17, 2015, in Aurora, Colo.

(AP Photo/David Zalubowski)

CSP said the first bus was carrying crew members for the performer Twin Shadow, while the other tour bus was carrying crew members of the country band Thompson Square. They were not traveling together, but both were heading to Denver to perform.

The fog was part of an overall system that brought snow into Denver and the rest of the Rockies region. We're not just talking about the mountains either. Salt Lake City saw 5.8 inches of snow late Tuesday night through Wednesday.

While roads in the city of Denver remained mainly wet due to warm ground temperatures and air temperatures in the low-mid 30s, 4.1 inches of snowfall was measured at the airport by Friday morning before precipitation turned to rain in the city.

Unfortunately, heavy snow and whiteout conditions contributed to a . Cheyenne had picked up 5.2 inches of snow through midnight Thursday night and up to 9 inches of snow was measured in Laramie, Wyoming as of early Thursday evening. Poor conditions lasted into Friday afternoon, leaving I-80 shutdown well over 20 hours.

By the time the snow is finished this weekend, some locations in the mountains and foothills west of Denver could see more than 3 feet of total snowfall. In the mountains of Utah where snow has tapered off, up to 45 inches was reported at Snowbird ski resort as of Thursday morning.

(FORECAST: )

Snow in April, and even May, is not uncommon in the Rockies and the adjacent High Plains. Denver has recorded its final measurable snow of the season during the first half of May in seven of the last 10 years.

Below are more photos from this spring snowstorm in the Rockies.