Up to 4 inches fell in Denver by Wednesday morning, with more falling in areas to the north. Downed power lines due to snow caused power outages, including one that shut down the University of Northern Colorado in Greeley.
Wall Street protesters continued to camp out under tarps, but two people had to be treated for hypothermia.
The taste of winter came as President Barack Obama makes his second visit to Denver in less than a month. The last time he visited some people passed out from the heat.
The same storm was also bringing snow to Utah and Wyoming, where it shut down a portion of Interstate 80 between Laramie and Cheyenne.