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

As another winter storm hits Western North Carolina and other regions, here's what to know about deciphering forecaster terms.

What is the polar vortex? This article explains what a polar vortex is in simple terms, how it influences winter weather in the U.S., and why meteorologists talk about it during major cold events.

A major weather pattern change underway across U.S. As we get into next week, the storm track looks really interesting.

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

In yet another sign that winter weather is either here or will be soon, the dreaded polar vortex is making news yet again. Its potential arrival in the United States over the next few weeks is cause ...

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

The polar vortex is sending arctic blasts and chilly temperatures to most of the United States, and states from Texas to Oklahoma could see snow, sleet and ice. As of Wednesday, Jan. 21, millions of ...

Frigid wind chills of -50 degrees and lower hit parts of the Midwest early this week – with some seeing high temperatures below 0 – all thanks to the polar vortex. But, what the heck is the polar ...

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

The polar vortex is sending arctic blasts and chilly temperatures to most of the United States, and states from Texas to Oklahoma could see snow, sleet and ice. As of Wednesday, Jan. 21, millions of ...