In yet another sign that winter weather is either here or will be soon, the dreaded polar vortex is making news yet again. Its potential arrival in the United States over the next few weeks is cause ...

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 ...

A fresh blast of cold Arctic air reportedly sent temperatures plunging below zero in parts of the upper Midwest this weekend after record cold hit the nation's Heartland last week. According to ...

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 ...

A major winter storm is impacting much of the nation east of the Rocky Mountains. The storm's intensity is caused by a combination of a stretched polar vortex, a wavy jet stream, and moisture from the ...