As Polar Vortex Freezes US, Satellites Track It from Space

It's winter in the United States, and swaths of the country are currently experiencing bitter cold brought on by a phenomenon nicknamed the polar vortex, a pattern weather satellites are watching closely. The National Weather Service is offering a blunt message about the cold weather, calling it "life-threatening." The cold temperatures are caused by Arctic air masses drifting farther south than usual, bringing biting winds that are pushing wind-chill temperatures in regions of a dozen states as low as minus 40 degrees Fahrenheit (minus 40 degrees Celsius). That's cold enough to cause frostbite in half an hour. More

(Source: Space.com - Feb 1)