Extreme Cold/Wind Chill in Rock Springs & Green River, Wyoming

Temperatures of minus 30 or below were commonplace across the region, including minus 35 degrees, three miles northwest of Rock Springs.

A combination of an arctic air mass, a clear sky, a long early January night and a deep, fresh snow pack brought frigid temperatures to much of western and central Wyoming. Four different counties recorded low temperatures under minus 40, including a low of minus 45 East of Rock Springs. All eleven counties in the County Warning Area recorded a temperatures of -30 or lower on the night of January 5-6, 2017.