Forecasters are warning of treacherous holiday travel and life-threatening cold for much of the US this week as an arctic air mass blows into the already-frigid southern United States.

“We’re looking at much-below normal temperatures, potentially record-low temperatures leading up to the Christmas holiday,” said Zack Taylor, a meteorologist with the National Weather Service.

The polar air arrives as an earlier storm system gradually winds down in the northeastern US after burying parts of the region under 61 cm. of snow. More than 80,000 customers in New England were without power on Sunday morning, according to poweroutage.us, which tracks outages across the country.

The incoming arctic front brings “extreme and prolonged freezing conditions for southern Mississippi and southeast Louisiana,” the National Weather Service in a special weather statement.

By Thursday night, temperatures will plunge as low as minus 10.6 Celsius in Jackson, Mississippi; and around minus 15 Celsius in Nashville, Tennessee, the National Weather Service predicts.

For much of the US, the winter weather will get worse before it gets better.

The coming week has the potential for “the coldest air of the season” as the strong artic front marches across the eastern two-thirds of the country in the days before Christmas, according to the latest forecasts from the federal Weather Prediction Center in College Park, Maryland.

The centre warned of a “massive expanse of frigid temperatures from the Northern Rockies/Northern Plains to the Midwest through the middle of the week, and then reaching the Gulf Coast and much of the Eastern US by Friday and into the weekend.”

In Atlanta, where temperatures dropped below freezing early Monday morning, forecasters are warning of even colder air by late in the week. The low Friday night in Atlanta will be around minus 10.6 Celsius with the high temperature Saturday still below the freezing mark at around minus 1.7 Celsius, the Weather Service projects.

Florida will not have a white Christmas, but forecasters are expecting that weekend to be unusually cold throughout the state with temperatures in northern cities such as Jacksonville, Tallahassee and Pensacola expecting lows of minus 3 Celsius on Christmas Eve, and highs of about 40 Celsius. Southern regions will remain much more moderate.