BISMARCK, N.D.—The deadly deep freeze enveloping the Midwest sent temperatures plunging on Jan. 30, to rival some of the most frigid spots in the world, triggering widespread closures of schools and businesses, and the canceling of more than 1,600 flights from Chicago’s airports.
The U.S. Postal Service even took the rare step of suspending mail delivery across much of the region. Hundreds of public schools and universities from North Dakota to Pennsylvania canceled classes as residents huddled inside amid one of the coldest air masses in years.
