The most unusually cold air in the Northern Hemisphere will be over the United States early next week, bringing dangerously frigid conditions.

However, a deep freeze, thanks to the polar vortex dipping down from Siberia, is about to bring even harsher arctic blast to nearly 300 million Americans starting this weekend. Maps show where and when the cold front will arrive.

A polar vortex is slated to sweep most of the continental US bringing winter storm warnings and a hazardous freeze to millions.

A blast of Arctic air is set to cover much of the United States with temperatures below freezing starting on Friday and into next week, impacting millions of Americans in nearly all of the contiguous states.

A brutal polar vortex is set to bury the Big Apple in snow Sunday and then deliver deadly single-digit temperatures that will feel like 15 degrees below zero. New

Americans were bracing Thursday for frigid temperatures that forecasters said could produce life-threatening conditions, with Donald Trump's inauguration expected to be the coldest in 40 years.

People living "basically anywhere from the Rockies eastward" will see extremely cold temperatures over the next several days, a meteorologist says.

Temperatures are expected to plummet over the weekend, bringing life-threatening conditions to large stretches of the United States. The polar vortex will send temperatures below freezing for much

NEWS has issued Weather Impact Days for Friday through Tuesday due to subzero temperatures, wind chill and snow.

Another blast of winter weather is expected in parts of the U.S. in the coming days, including bone-chilling wind in the Northern Plains and unusual snow and ice in the Gulf Coast area.

Frigid arctic air due to a polar vortex is about to send temperatures plunging for millions of Americans across the U.S., and that could lead to one of the coldest Inauguration Days seen in decades.