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

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

Ben Gelber, a meteorologist for NBC4 in Columbus, Ohio, and a Pocono native, said the polar vortex is a large, circular pool ...

A fresh blast of Arctic air is poised to spill across a wide swath of the United States, and the latest polar vortex map ...

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

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

A fierce Arctic blast of bitterly cold air is poised to overtake much of the central, eastern and southern U.S. over the next ...

With over 170 million Americans facing below average temperatures, even colder air may be on the horizon thanks to the ...

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

The frigid stream of air that plunged down into the Central U.S. this week is breaking cold records from South Dakota to Texas, with temperatures in the single digits setting records in many locations ...