A dangerous and potentially life-threatening stretch of cold weather has much of the U.S. on alert as a lobe of the polar vortex invades ... FOX Weather More than 30 states are now on alert ...

The study published by Cohen and his co-authors suggested warming Arctic temperatures have been disrupting the polar vortex more often since 1990 and sending more frequent cold blasts into the U.S ...

A weak vortex allows more arctic air and stormy patterns to develop here in the U.S. A strong one keeps arctic outbreaks at bay. Unfortunately, it is something that cannot be well predicted more ...

A lobe of the polar vortex will arrive in the United States this weekend, bringing the lowest temperatures in years and snow and ice to the East and Deep South.

January has already been colder than average in most states east of the Rocky Mountains for the first time in two years — and now, more frigid air is coming. A lobe of the polar vortex ...