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

"Bitter cold could linger through the end of the month," the Weather Prediction Center said in an update on Monday.

Deep penetration of cold temperatures and a coastal storm will bring bomb cyclone and polar vortex into your newsfeeds.

The west half of the country, including the Midwest, will start to warm up. But that won't be the case for the East Coast. Here's the forecast.

Temperatures could fall below -20 F across certain parts of North Dakota and Minnesota.

A chilling polar vortex is set to bring snow and ice to the South and East this week. We show where.

A powerful winter storm, influenced by a polar vortex, is impacting much of the U.S., bringing heavy snow, ice, and extreme ...

Meteorologists warn that a stretched polar vortex could bring severe winter weather to much of the United States.

Here’s the wind chill chart. Notice the four shadings, indicating how long it will take for frostbite. When we get to wind ...

A significant portion of the U.S. is experiencing below-average temperatures due to a disrupted polar vortex, affecting over ...

Environment Canada has issued weather warnings for most of Canada over a 'high or moderate impact level' cold blast that is ...