Temperatures will plummet by up to 40 degrees this weekend as an arctic blast spreads across much of the U.S., including the Deep South.

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.

Sign up for the Morning Brief email newsletter to get weekday updates from The Weather Channel and our meteorologists.J​anuary's shivering weather pattern east of the Rockies shows no signs of letting up as we head into the month's final stretch.