At least 23 people died as a result of the bitter cold brought on by the Polar Vortex that ushered in the coldest Arctic air the Midwest and Northeast United States has seen in decades.

Iran Press/America: Though school closures continue and mail delivery is still on hold in some states due to the cold, temperatures are expected to turn milder by the weekend, including parts of the upper Midwest that could be 60-plus degrees warmer than they were at the worst of the cold snap.

Several major Midwest universities remain closed Thursday, including the University of Notre Dame, the University of Minnesota, the University of North Dakota, the University of Wisconsin, the University of South Dakota and Iowa State University, Associated Press reported.

A man's eyebrows and eye lashes are frozen after walking along Lake Michigan's ice covered shoreline as temperatures dropped to -20 degrees

In a rare move, the cold prompted the US Postal Service to ignore the popular saying: "Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds." Instead, the service once again suspended service Thursday to parts or all of several Midwest states, including Michigan, Indiana, Illinois, Ohio and Pennsylvania.

More than 3000 flights have been canceled as of Thursday evening, including more than 1,400 at Chicago's O'Hare, according to Flight Aware.

Meanwhile, a state of emergency remains in effect in much of the Midwest and Northeast United States.  101/ 211 / 202

 

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Photos: Unusual cold in Europe

 

A man
A man