Even in a warming climate, brutal cold snaps still hammer parts of the U.S., and a new study uncovers why. High above the Arctic, two distinct polar vortex patterns — both distorted and displaced — ...

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 ...