During winter in the Northern Hemisphere, the polar vortex can often expand and send cold air south, often referred to as an ...

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

To understand what Americans are experiencing with this winter blast, we need to look more than 20 miles above the surface of ...

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.

The North Pole is surrounded by a massive circular upper-air weather phenomenon in the Arctic called the polar vortex. It is ...

The polar vortex is forecast to weaken unusually early, and that could lead to more persistent cold weather in at least parts of the U.S. in December. Last week, almost 100 daily record lows were tied ...

A shift in the polar vortex has forecasters watching closely as the coldest air of the season approaches. Here's what to know in Georgia this weekend.

A Polar Vortex brought temperatures so cold in January 2014 that it froze Niagara Falls. Signals of a rare sudden stratospheric warming in the next two weeks have some forecasting an imminent Arctic ...

When the polar vortex breaks, Artic air come south. Here's what to know right now.