The polar vortex, a high-altitude ring of westerly winds that usually keeps Arctic air locked near the pole, is showing signs of unusual weakening. If that circulation falters or collapses, the result ...

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 ...

Despite a warming climate, bone-chilling winter cold can grip parts of the U.S. In a study appearing in Science Advances, researchers found that two specific patterns in the polar vortex, a swirling ...

When the polar vortex stumbles, the weather at ground level can pivot from mild to brutal in a matter of days. A circulation that usually spins quietly above the pole can suddenly send lobes of Arctic ...

An Arctic blast could bring freezing temperatures and heavy snow to Kentucky around Thanksgiving weekend. A "sudden stratospheric warming" event may disrupt the polar vortex, potentially causing ...

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 ...