The sun rises over downtown Pittsburgh and a partially frozen Allegheny River on Thursday. The temperature in Pittsburgh dropped to minus 4 late Wednesday, breaking an 85-year-old record low for Jan. 30 of minus 1 degree.
New York State police investigate a 21-vehicle pileup in Batavia, New York, on Wednesday. Police say the crash shut down the highway where heavy snow and high winds made driving treacherous.
Mike Calen, left, and Steve Goyette, right, prepare to tie off as the ice-covered fishing boat Buzzards Bay arrives at New Bedford, Massachusetts, harbor due to the extreme cold conditions on Thursday.
Geese huddle in the water as the sun rises at the harbor in Port Washington, Wisconsin, on Wednesday.
Flight information screens show flight status information at O'Hare International Airport in Chicago, on Thursday, when hundreds of flights were cancelled. Disruptions caused by the cold will also persist, including power outages and canceled flights and trains.
David Grall exhales as he clears a path to his mailbox on Thursday in the town of Polk, Wisconsin. The painfully cold weather system that put much of the Midwest into a historic deep freeze was expected to ease Thursday, though temperatures still tumbled to record lows in some places.
The James J. Versluis ice-breaker tug boat travels through the Chicago River in Chicago on Wednesday.
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