Reinforcing shots of cold air will continue to dive into the Northern Plains and Midwest this week. The coldest air will move in Friday, Saturday and Sunday, and wind chills will drop well below zero for many, including Minneapolis, Chicago, Kansas City and St. Louis. Watch this to see how cold it will get.

Another atmospheric river is slamming into the Pacific Northwest. While some of these can be beneficial, this one may be largely hazardous for flooding rain. Here's the latest forecast.

A weak La Niña is poised to give northern U.S. ski regions a major leg up this December, stacking the deck with storm potential and fresh powder. From the Cascades to New England, the northern tier looks ready to carve ahead, while southern portions of the Rockies and Appalachians may struggle to keep up.

When conditions are cold, wind can strip away the warm layer of air insulating your skin. Because of this, wind makes the effective temperature to your body colder than the actual air temperature.

Frostbite isn’t just a winter nuisance, it’s a fast-moving health threat as cold fronts surge across the country and wind chill values plummet to dangerous levels. We’re explaining how quickly frostbite can set in, who’s at highest risk and the simple steps experts say can prevent a life-threatening emergency.