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The coldest air in at least 25 years is pouring into the Midwest on Wednesday, promising to topple records and prompting officials to warn of “life-threatening” temperatures.

Norris Camp, in northwest Minnesota, was the coldest location in the Lower 48 so far, after temperatures there dropped to minus-48 degrees this morning, measured by an official with the Minnesota Department of Natural Resources. With winds blowing at 5 to 10 mph, wind chill would have been around minus-65 degrees. Several other locations in Minnesota and North Dakota plunged to dangerous lows, including Warren, Minn. (minus-47); Lisbon, N.D. (minus-46); and Park Rapids, Minn. (minus-42).

At the National Weather Service in Duluth, “there’s talk of making a run at the state record” Wednesday night, meteorologist Geoff Grochocinski told The Post. Minnesota’s current record low is minus-60, and it was set near the city of Tower in 1996. The conditions that have to line up in order for that temperature to occur Wednesday night are a long shot, but not impossible.

According to a news release from the Duluth office, “if winds can subside, and skies clear Wednesday night, as is currently forecast, some of the historically favored cold locations in interior northeast Minnesota, and possibly northwest Wisconsin could approach all-time record values.”


Marius Radoi keeps his balance as he walks on the edge of Lake Michigan's shoreline as temperatures dropped to minus-20 degrees on Wednesday in Chicago. (Joshua Lott/AFP/Getty Images)

Wednesday was the second-coldest day in Chicago’s history. The maximum temperature, minus-10, was set just after midnight, and then the mercury dropped to minus-24 later in the morning. The combination of those extremes results in a daily average of minus-17, just short of Dec. 24, 1983, when the average temperature was only minus-18 in the Windy City.

Another significant record is in jeopardy in Chicago; Thursday morning lows will plummet close to the city’s record low temperature of minus-27, set on Jan. 20, 1985. And the state record in Illinois — minus-36 degrees set in Congerville on Jan. 5, 1999 — could also fall Thursday morning somewhere in Northern Illinois, west of Chicago. Conditions are particularly favorable for state records to fall this week, with clear skies and fresh snow on the ground.

“[T]he message is to avoid outdoors if one can and if not, this is the day to dress as absolutely warm as possible,” the Weather Service office serving Chicago wrote. It called the wind chills in northern Illinois “about as frigid and dangerous ... as can be.”

Tom Skilling, a longtime meteorologist at Chicago’s WGN-TV, says describing the weather as brutal is an understatement.

“Lake Michigan took on the appearance of a boiling cauldron as air of minus 20 degrees and colder made contact with water sitting just above the freezing level,” said Skilling in his report. “I’ve lived here 40 years and never until today have never seen a more spectacular display of ‘sea smoke.’”

The cold air is riding behind an Arctic front that brought several inches of snow to the same region over the weekend. The pure white ground will enhance the chill, as sunlight reflects off the snow and back to space instead of being absorbed into the ground where it could warm things up. If those conditions line up, they could “easily push” temperatures to minus-35 to minus-39 in Northern Illinois, the National Weather Service said Tuesday, which would jeopardize if not topple the state’s coldest low.

Several records for Jan. 30 were broken at sunrise, including two set in 1966 in Northern Illinois: Chicago’s record of minus-15 and Rockford’s at minus-19. The temperature in both of those cities was around minus-20 and still falling Wednesday morning.

Other all-time records in jeopardy this week:

  • Rockford, Ill. — Minus-27 set on Jan. 10, 1982
  • Cedar Rapids — Minus-29 set on Jan. 15, 2009
  • Dubuque, Iowa — Minus-32 set on Jan. 7, 1887
  • Moline, Ill. — Minus-28 set on Feb. 3, 1996

A look at the Polar Vortex and how it shifted

The polar vortex, at least a portion of it, is causing the extreme cold. A lobe of the bitterly cold Arctic air descended into the Lower 48 this week.

“Most of the time, [the polar vortex’s] harsh conditions are out of reach,” the Capital Weather Gang’s Matthew Cappucci explains. “But every so often, lobes of it pinch off from the main flow and crash south. This can lash the Lower 48 with piercing shots of cold, intense bouts of storminess and bitter wind chills well below zero.”

While actual temperatures drop to negative double digits this week, media have been clamoring to find exotic locations that will be warmer than the Midwest. Antarctica, for example, will be a balmy 10 degrees Thursday morning when Minneapolis drops to around minus-30. But it is summertime in the Antarctic, so that shouldn’t be surprising. What is surprising, at least meteorologically, is that the Midwest will be colder than the North Slope of Alaska on Thursday morning. Utqiagvik, formerly known as Barrow, will drop to around minus-20 — 10 degrees warmer than parts of Minnesota, Wisconsin and Illinois will be at the same time.


Forecast low temperature for Thursday (Tim Meko/The Washington Post/Tim Meko/The Washington Post)

Even if all-time records are not broken, the National Weather Service in Chicago is calling this week’s forecast “life-threatening extreme cold” that “can lead to rapid onset of frostbite and hypothermia.” A recent report from the Centers for Disease Control and Prevention found that cold weather is responsible for the majority of weather-related fatalities.

The wind chill temperature is more than a catchy forecast term. The wind blows away the insulating layer of warm air around us generated naturally by our bodies. Wind chill attempts to quantify the effect in terms of how it feels on our skin, which is why you’ll sometimes hear it called the “feels like” temperature. A wind chill of minus-20 degrees can cause frostbite in as little as 30 minutes.

Dozens of records could be broken this week as the temperatures fall. Forecasts suggest that Wednesday’s high temperatures in the Midwest might be some of the coldest on record for certain locations, and Thursday morning’s low temperatures could also set records.