The first of three rounds of bitter air has arrived, threatening record lows in cities from the Midwest to the Northeast.

"With rounds of sub-zero temperatures expected in portions of the Plains and Midwest, widespread lows in the teens and 20s ...

A polar vortex broke, and severe temperatures are set to dominate most of the United States, including the Midwest, in the ...

As one blast of Arctic air pushes out to sea, already a new surge of cold air, driven by a breakdown of the polar vortex, is ...

Feeling that sudden chill? A triple polar vortex is sweeping across parts of the U.S. Here’s what that means — and where it’s ...

Thanks to the polar vortex, the first half of December will bring multiple waves of Arctic air to the U.S. Here's what to ...

Frigid Arctic air is pushing south into the United States, and fortunately, it doesn’t look like freezing temperatures will ...

A polar vortex brings frigid temperatures and a light chance of snow Friday. High winds could become dangerous combined with ...

The Upper Midwest and Northern Plains have been hit by Canada's freezing temperatures. On Thursday, Dec. 4, wind chills ...

A strong polar vortex doesn't cause cold weather — it does the opposite. Here's what to know about polar vortices, how they ...

Arctic wind patterns create a sort of wall around the pole that prevents frigid air from trickling southward. That wall that ...

A strong polar vortex doesn't cause cold weather — it does the opposite. Here's what to know about polar vortices, how they ...