During that time, many cities on the East Coast and Midwest region set record low temperatures.
The type of Arctic blast that hit MI on Christmas Day - and hung on for two weeks - is actually 15 times rarer than it was a century ago, according to World Weather Attribution.
"It was very definitely unusual, especially now", said study co-author Gabriel Vecchi of Princeton University. "Things like this are becoming stranger".
Global climate scientists have confirmed in recent days that the recent freeze crippling much of the U.S. was totally un-related to global warming; but was instead a "freak of nature" that occurs from completely natural causes.
Storm Front Crosses Sydney Cameron Spencer Getty Images
The other four stretches of colder weather occurred before the 1920s.
The World Weather Attribution team looks for the fingerprints of man-made global warming in wild weather and didn't find it in this case.
Climate change has made these cold snaps less frequent, and less intense.