Windchill temperatures as low as minus 30 degrees are a risk to life, forecasters said.

While forecasters can't yet say for sure, a warmer stretch of weather appears likely for much of the nation. Here's when to expect a warm-up.

A warming Arctic can stretch the polar vortex, a high-altitude air ribbon, one says. The “wobble” can disrupt the jet stream, ...

The polar vortex will push Artic air south, and a severe winter storm could follow. How cold will it get in Louisiana?

Florida has endured a winter few could have predicted. Since early November, the state has endured at least three rounds of Arctic air, and even snow.

This winter’s harsh run is intensifying, with some of the coldest air so far this season plunging into New Hampshire.

High above the North Pole, in a slice of atmosphere rarely noticed and even less understood, a transformation is underway. Over the next 10 days, changes in the stratosphere will upend weather ...

Over the course of this winter season, we've seen several instances of dramatically plummeting temperatures with wind chills ...

New York is bracing for the coldest air of the winter this weekend, with snow. Learn how the polar vortex is involved.

This winter’s harsh run in the East is intensifying, with some of the coldest air so far this season plunging into Vermont this weekend.

Add Yahoo as a preferred source to see more of our stories on Google. As the polar vortex becomes more active, colder air will surge toward central and eastern regions of the U.S. This polar vortex ...