The Polar Vortex is expected to be impacted by a Sudden Stratosphere Warming, bringing cold air to the eastern US.
Much below normal temperatures should persist across the eastern U.S. into early February before moderating slightly.
Much of the nation east of the Rocky Mountains is hunkered down for what could be the worst winter storm of the season.
Alabama braces for another polar vortex blast bringing well below freezing temperatures. How cold will temperatures get? Here's what to know.