A winter buzzword, explained.

Bitingly cold Arctic air keeps pummeling the U.S. with ruthless cold snaps—despite warming winters nationwide. A study explains why: the solution lies far above your head, in the upper atmosphere ...

With the warming of winter creeping in, extreme cold events were expected to fade, but that was not the case. Though certain cold spells were normal variations in climate that felt cold against a hot ...

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 ...

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 ...