Much of the U.S. will see temperatures plummet 20 to 40 degrees below average when a major Arctic outbreak bringing frigid temperatures sweeps through the country.

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.

Charlotte faces “dangerous” low temperatures and wind chills from an approaching Arctic air mass, National Weather Service meteorologists said in an alert Thursday. “ Confidence is high that it will be very cold next week,” forecasters said earlier on the social media site X.

An arctic blast will send temperatures across the United States plummeting as bitterly cold air that originated in Siberia will arrive from Canada by week’s end, bringing with it dangerously cold wind chills for millions of Americans.