An arctic air mass sprawling across the eastern, central and parts of the western U.S. on Monday will channel temperatures 20-30 degrees below already historically cold January averages and was poised to slam parts of the South with a disruptive winter storm.

Amid a dangerous arctic blast over much of the U.S. this week, snow and ice may bring major travel disruptions and power outages in the South, forecasters warned.

An already active winter is about to shift into overdrive as a trio of storms over the weekend and into next week deliver snow to the Midwest, East and possibly as far south as the Gulf Coast.