00:45 Snow Causes Massive Pileup on I-80 in Laramie County, Wyoming Images of massive pileup, caused by snow, in Laramie County, Wyoming.

A 150-mile stretch of Interstate 80 between Cheyenne and Rawlins, Wyoming, reopened Friday night, more than 20 hours after major wrecks involving dozens of semi trucks forced police to close it down.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/WHP_FridaySemiI80_825.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/WHP_FridaySemiI80_825.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/WHP_FridaySemiI80_825.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > Semi trucks are stacked against one another along I-80 in Wyoming. (Wyoming Highway Patrol) (Wyoming Highway Patrol)

Blinding, blowing snow hit southern Wyoming Thursday, creating impossible driving conditions that police say likely led to a series of three wrecks along the interstate. More than 30 commercial vehicles and 12 passenger cars were involved.

Photos show the semi trucks piled up on one another. No one was killed, but about a dozen people were hospitalized.

(FORECAST: Spring Storm Slams Rockies )

Poor weather continued to hammer the area into Friday, complicating the cleanup effort, and forcing WHP to keep the interstate shutdown. They urged anyone planning to drive through the area to check www.wyoroad.info beforehand.

The system brought winter-like weather into the Rockies and High Plains Thursday into Friday, dusting the Denver foothills with a few inches of snow, and dumping at least 45 inches at Snowbird ski resort in Utah.

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