Though a fierce blast of cold air froze the central U.S. Friday, what's coming next week will be even worse:

Using words such as "life-threatening," "dangerous," "brutal," and "unprecedented," the National Weather Service is preparing us for the extreme cold that's forecast to roar into the U.S. next week.

"The coldest air of the season will plunge the upper Midwest and Great Lakes into life-threatening conditions" next week, the weather service said Friday. The cold will be most intense from Tuesday through Thursday.

And although the worst of the cold will be over the north-central region, practically the entire eastern two-thirds of the nation will see freezing temperatures, all the way down to central Florida. That's nearly 200 million people.

On Friday, the numbing cold prompted officials to close schools in several states. This included the Milwaukee public schools, Wisconsin's largest school district.

The deep freeze caused organizers of the Winter Carnival in Minnesota to cancel several events.

What's in store next week is even more ferocious: Wind chills of 55 degrees below zero are possible in parts of the upper Midwest, while actual air temperatures will dip to 30 degrees below. The wind chill, which describes the effect of wind and cold temperatures on exposed skin, can cause frostbite within minutes at those temperatures.

The Weather Channel warned that by the middle of next week, daytime highs may not rise above zero in parts of the north-central U.S. and may not rise out of the single digits in the Ohio Valley.

The frigid invasion of cold air has been called “Barney” by some forecasters. This is because forecast maps use purple to illustrate extremely cold temperatures, weather.us meteorologist Ryan Maue said.

While all-time cold temperature records aren't expected, many spots will see their lowest temperature on record for January 29th or 30th.

The cold is courtesy of our old friend the polar vortex, which is expected to become displaced from the Arctic Circle and plunge down to near the upper Great Lakes, according to AccuWeather. Meteorologist Judah Cohen of Atmospheric and Environmental Research, looking ahead to next week's forecast, said that "the polar vortex is without a doubt sitting on top of the Great Lakes."

The University of Maine’s Climate Reanalyzer notes that the temporary icy cold doesn’t disprove global warming, despite what some non-scientists may claim. On Friday, the globe as a whole was 1.08 degrees warmer average.

"Yes, it's cold in the U.S. Midwest and parts of Canada," noted meteorologist Steve Bowen of insurance firm Aon. "But, overall, the globe is still anomalously warm. Check out Alaska, Africa, Asia, and Australia."

Some good news: The intense cold won't last too long: AccuWeather said the harsh cold should ease somewhat across the eastern half of the U.S. during the first weekend of February.

Contributing: The Associated Press