It’s freezing out there.
A blast of Arctic air has gripped the vast middle of the United States with the coldest temperatures in two decades, causing at least four deaths, forcing businesses and schools to close, and canceling thousands of flights.
Temperatures were 20 to 40 degrees F. below average in parts of Montana, North and South Dakota, Minnesota, Iowa, Wisconsin, Michigan, and Nebraska, the National Weather Service said.
More than half the flights at Chicago’s O’Hare International Airport were canceled as fuel supplies froze, leaving crews unable to fill aircraft tanks.
The polar vortex — the Northern Hemisphere’s coldest air — which hovers over the polar region in winter but can be pushed south, was moving toward the East Coast, where temperatures are expected to keep falling into Tuesday.
New York Gov. Andrew Cuomo declared a state of emergency, announcing that parts of the New York State Thruway in western New York would be closed because of extreme winter weather conditions.
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