A polar vortex dipping down from Siberia will bring a cold front with frigid temperatures to nearly 300 million Americans. See maps of the arctic blast.

A new blast of Arctic air sweeping from north to south will bring bone-chilling temperatures to millions of Americans this weekend and next week.

Dangerously cold weather will put much of the United States into a deep freeze over the weekend as temperatures are expected to plunge by up to 40 degrees behind an Arctic air mass.