Major cities across the Northeast and Midwest are facing temperatures 10-20 degrees below average, according to forecasters.

The polar jet stream, which is affected by the polar vortex above it, has become quite wavy, allowing Arctic air to ...

In the coming weeks, cold air will continue for parts of the U.S. thanks to the influence of the polar vortex.

Michigan is set for several days of frigid temperatures and heavy lake-effect snow as Arctic air continues its slow march across the eastern U.S.

Cold temperatures are expected to last through the end of the month — and forecasters say that there's a potential for snow ...

A major polar vortex is about to hit the US and could bring weeks of frigid temperatures for millions, with even a chance of ...

Don't let the incoming string of relatively warm days in the greater Philadelphia region fool you; the polar vortex is still ...

The Polar vortex is causing temperatures to plummet dangerously across the Philadelphia region, and frostbite could become a ...

Arctic air originates near the polar regions and is among the coldest air masses on Earth. It typically stays locked in ...