These severe cold events occur when the polar jet stream – the familiar jet stream of winter that runs along the boundary between Arctic and more temperate air – dips deeply southward, bringing the cold Arctic air to regions that don’t often experience it.

Most of the U.S. will enjoy milder temperatures on Thursday, but the warmup will be brief as a polar vortex will send temperatures tumbling below freezing for most of the nation starting this weekend.

It’s going to be a rude awakening tomorrow — a full taste of winter, for sure,” National Weather Service meteorologist says

Are you ready for the coming arctic storm? Here’s the latest Colorado weather forecast and everything else you need to know ahead of extreme cold.

People living "basically anywhere from the Rockies eastward" will see extremely cold temperatures over the next several days, a meteorologist says.

VIRGINIA BEACH, Va. — Looking ahead to next week, a major arctic blast is expected to settle into Hampton Roads and Mid-Atlantic. The region will likely deal with the coldest weather so far this winter season.

Wind chill values are expected to drop below 10 degrees, with some locations seeing wind chills closer to zero. Forecasters note a slight chance of snow flurries Saturday.

The polar vortex is always around. It is a channel of strong winds high up in the atmosphere that circles the poles. One over the North Pole and one over the South Pole. When the vortex is at it's strongest, the vortex is well defined and has a single circular shape to it.

Cities across the U.S. are bracing for cold temperatures as a polar vortex arrives, bringing temperatures down to much below normal for mid-to-late January. Parts of Utah are on the "very western fringe" of a cold front that will bring in air from the Arctic.

A potent shot of Arctic air starts settling in Monday as a massive dip in the jet stream pulls in frigid air across the entire eastern half of the country. Temperatures are set to drop as low as 20 degrees below average Tuesday and Wednesday with highs only reaching the teens, with lows in the single digits and even plunging below zero.

People living "basically anywhere from the Rockies eastward" will see extremely cold temperatures over the next several days, a meteorologist says. That includes Kansas City, which is set to host a Chiefs playoffs game this weekend.