What caused the avalanche spotted by drivers in Colorado?

The avalanche spotted by drivers along I70 in Frisco, Colorado on Monday was fueled by the coldest air of the season. This dramatic winter event occurred as part of an intense winter storm affecting 25 states across the country, bringing blizzard conditions and severe cold nationwide. The harsh weather system created hazardous conditions throughout the heartland, resulting in road closures and safety alerts affecting millions of Americans. In mountainous regions, snowfall exceeded two feet, creating the perfect conditions for avalanches like the one witnessed along the interstate.