A polar vortex dipping down from Siberia will bring a cold front with frigid temperatures to nearly 300 million Americans.
A lobe of the polar vortex will arrive in the United States this weekend, bringing the lowest temperatures in years and snow and ice to the East and Deep South.
Another blast of winter storms is closing schools, snarling flights and putting millions of residents on alert across parts of the Deep South and south-central U.S. The National Weather Service says ...