The west half of the country, including the Midwest, will start to warm up. But that won't be the case for the East Coast. Here's the forecast.

The west half of the country, including the Midwest, will start to warm up. But that won't be the case for the East Coast. Here's the forecast.

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

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

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

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

A fresh blast of Arctic air is poised to spill across a wide swath of the United States, and the latest polar vortex map ...

The polar jet stream, which is affected by the polar vortex above it, has become quite wavy, allowing Arctic air to ...

This winter, the Northern Hemisphere has been suffering from extreme cold. In South Korea, an unusually prolonged cold wave ...