A winter buzzword, explained.

Add Yahoo as a preferred source to see more of our stories on Google. In an early sign of the winter weather that's coming, the dreaded polar vortex is making news yet again. The polar vortex is ...

A Polar vortex has covered the Philadelphia region under a canopy of frigid temperatures, but many people may not realize what a Polar vortex actually is, and the dangers — like frostbite — such ...

Michigan is experiencing frigid temperatures and heavy snow due to a dip in the jet stream, not the polar vortex. The polar vortex is a large-scale cyclone of cold air that typically stays far north ...