After the hottest year on record, cold is making a comeback.
Four people have died in the Midwest as records were set in the Chicago Botanic Garden (minus 3 degrees Fahrenheit ) and Cook County, Minn. (minus 34 degrees Fahrenheit), according to The New York Times.
The National Oceanic and Atmospheric Administration (NOAA) notes there is a daily cycle of heating and cooling, "but the pattern is clear: much of the U.S. is pretty cold."
This video from the NOAA shows the wave of Arctic air that's caused temperatures to fall dramatically. Areas colored blue are below freezing.
Andrea Thompson of OurAmazingPlanet notes a kink in the jet stream brought the deep chill, which is expected to meet with some warmer air this weekend to create some snow and icy weather as temperatures rise about freezing.
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