Weakening polar vortex to deliver more record-breaking cold to millions in Midwest and Northeast this weekend

Cold weather alerts are already in effect for much of the Upper Midwest through the weekend.

The first of two arctic blasts of air being delivered late this week has arrived for the Northern Tier of the country, as a second more powerful punch of air arrives Saturday and Sunday for the Midwest and Northeast. 

Cold weather alerts are already in effect for much of the Upper Midwest through the weekend. 

An Extreme Cold Warning is in effect across parts of northeastern Montana and northwestern North Dakota

WEEKEND WINTER STORM TO BRING SNOW FOR MILLIONS ALONG I-95 CORRIDOR WITH BITTER COLD FROM POLAR VORTEX

Meanwhile, cold weather advisories stretch from Montana to Wisconsin

High temperatures will be in the single digits and teens from the Upper Midwest into northern New England. Across the Central U.S. and Tennessee River Valley, highs will be in the 20s and 30s, according to the FOX Forecast Center. 

Wind chills will heighten the effects of the bitter cold, where cities from Minneapolis, St. Louis, Nashville and all the up to Buffalo, New York, will see temperatures 20-30 degrees below average. 

THE SHORTEST DAY OF YEAR IS APPROACHING: WHAT YOU NEED TO KNOW ABOUT THE WINTER SOLSTICE

By the weekend, both Saturday and Sunday will feature some of the coldest air of the season for the country.

More severe impacts will come overnight Saturday into Sunday morning across the North, as lows will fall into the negative teens from North Dakota through Minnesota, Wisconsin, and Iowa.

WHAT IS HYPOTHERMIA AND WHAT CAN YOU DO TO PREVENT IT?

The FOX Weather Center said that once winds are factored in, wind values will drop alarmingly low, likely warranting Extreme Cold Warnings into the Northeast as well. 

The center warns that these levels of extreme cold can be very dangerous, as frostbite or hypothermia sets in within minutes.

HOW TO WATCH FOX WEATHER

By early next week the cold grip will push east, and the frozen areas will slowly return to closer to average temperatures.