As the U.S. prepares to take on another bout of cold weather, the term "polar vortex" is getting thrown around. But what is ...

Meteorologist Sven Sundgaard predicted this wacky winter weather back in October, and he explains what's happening now and ...

Meteorologists warn that a stretched polar vortex could bring severe winter weather to much of the United States.

Much of the nation east of the Rocky Mountains is hunkered down for what could be the worst winter storm of the season.

The majority of the United States will experience chilling temperatures due to a blast of arctic air from Canada. The Midwest ...

Temperatures could fall below -20 F across certain parts of North Dakota and Minnesota.

After this weekend's snow storm moves out, cold Arctic air will move in.

Tens of millions of people are in the path of a major winter storm. Federal cuts threaten efforts to understand the causes of such weather.

Welcome to the Frozen Apple. Temperatures in New York City have remained below freezing since Friday — and they’re expected to stay that way until at least early next week as arctic air has settled ...

A collapse in the polar vortex is letting Artic air come here. What that means, and why it happens.

Niagara Falls turns into a frozen wonderland as a powerful polar vortex pushes temperatures below -20°C, freezing mist ...