Brian Brettschneider, a climatologist with the Western Regional Climate Center, said the eastern half of the United States could usher in 2018 as the coldest New Year in 70 years.

“The last four runs of the GFS [Global Forecast System] show the eastern half of the Lower 48 ringing in the New Year with the lowest average temperature in at least 70 years – edging out 1977 by just over 2°F,” Brettschneider tweeted this week.

The last four runs of the GFS show the eastern half of the Lower 48 ringing in the New Year with the lowest average temperature in at least 70 years – edging out 1977 by just over 2°F. @capitalweather pic.twitter.com/efXAzn2weM — Brian Brettschneider (@Climatologist49) December 29, 2017

Weather.com reported:

With temperatures forecast to be around 10 degrees, this could be the second-coldest New Year’s Eve ball drop on record in New York City, with subzero wind chills possible. Subzero low temperatures will likely engulf the northern and central Plains, upper Midwest, Great Lakes, Ohio Valley, parts of New York state and New England through at least Tuesday.

If you live in the eastern two-thirds of the U.S. you face some of the coldest New Year's Eve and New Year's Day weather in many decades: https://t.co/G0w8PUKTWt — Capital Weather Gang (@capitalweather) December 31, 2017

Polar pain. Look at the wind chills New Year's Day morning in eastern U.S. Below freezing everywhere but Florida peninsula. Per @JamesSinko, 156 million Americans under wind chill alerts. More info: https://t.co/G0w8PUKTWt pic.twitter.com/EhAs68e9YV — Capital Weather Gang (@capitalweather) December 31, 2017

The Washington Post reported that the cold weather in the U.S. is the most “extreme” since February of 2015:

[It] will produce dangerously low temperatures and wind chills over large portions of both the central and eastern United States. On the morning of New Year’s Day, the National Weather Service predicts the nation’s average low temperature to hover around minus-12.22 Celsius (10 degrees Fahrenheit), with about a third of locations below zero. These temperatures, compared to normal, will be the coldest in the world.

The Capital Weather Gang tweeted about the wind chill accompanying the frigid weather.

“Polar pain. Look at the wind chills New Year’s Day morning in eastern U.S. Below freezing everywhere but Florida peninsula. Per @JamesSinko, 156 million Americans under wind chill alerts,” the tweet said.

The Capital Weather Gang retweeted a tweet from a weather watcher:

“As @ChrisClimate and @CaradhrasAiguo point out, this is also the coldest high temperature in December for DC since Dec 24, 1989! @capitalweather.”