The polar vortex is essentially a large area of low pressure and cold air surrounding both of Earth’s poles. It constantly sits over the poles but expands in the winter.

The polar vortex is a broad region of freezing air that lives above the North Pole. It can make for frigid weather when the jet stream, which usually holds it in place, bends and lets that cold ...

The science behind the polar vortex is incredibly complicated, and we've only recently begun to understand how changes at our planet's poles impact weather at more moderate latitudes.

The polar vortex – everyone's favorite wintertime whipping boy – is actually a gigantic, circular area of cold air high up in the atmosphere that typically spins over the North Pole ...

A researcher expects the polar vortex to strengthen over the next two weeks. This has a big impact on our day-to-day weather here in the Great Lakes region and even the Northeast. Judah Cohen ...

The polar vortex split will help cause temperatures to plummet and potentially set the stage for some snowstorms. A recent strong "sudden stratospheric warming" event has caused the vortex to weaken.

The polar vortex appears to be on the move. That’s because stratospheric warming is occurring at high altitudes above the North Pole, resulting in a spike in temperatures.

We've mentioned the polar vortex several times in recent days. We've said, for instance, that it's "a low pressure system that's usually whirling around the North Pole but has weakened and come ...

The stratospheric polar vortex is smoother, smaller and more circular. It doesn’t exist year-round — instead it’s a whirlpool of frigid air that forms in the fall as the upper atmosphere cools.