Much below normal temperatures should persist across the eastern U.S. into early February before moderating slightly.

Deep penetration of cold temperatures and a coastal storm will bring bomb cyclone and polar vortex into your newsfeeds.

A stretched polar vortex will bring subzero temperatures and heavy snow to 230 million Americans. Michigan utility customers ...

The greater Philadelphia region will experience no weekend letup in the prolonged cold snap gripping the area.

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

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

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.

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

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.