For once in a weather story, superlatives might be an understatement.
The Midwest is currently dead-center in the eye of a "polar vortex," a weather pattern in which some of the coldest air on the planet clenches a beyond-icy fist on America's heartland.
The air, ironically, was pushed southward due to a warm patch of water near Alaska. That warm air, in effect, blocks pacific winds from reaching the arctic, as Mashable explains: "This allows air from the Arctic to sit undisturbed in northern Canada, becoming colder and colder before flowing 'like molasses' down south through Canada and into the United States."
Now, imagine that the molasses is around minus 20 degrees Fahrenheit.
So what happens at temperatures that cold?
1. The antifreeze in your car could freeze. This popular brand will freeze at minus 34 degrees. The coldest temperature recorded in the country Monday afternoon was minus 36 in Crane Lake, Minn. There, you have to start calling it "freeze." In the rest of the Midwest, however, most overnight lows will only reach the negative mid-teens—perfect temperatures for freezing whole bottles of vodka (which freezes at minus 16.51 degrees).
2. You can imagine what it is like to live on Mars.
3. At minus 20 degrees and with 30 mph winds, frostbite occurs in six minutes. (Use this grim frostbite calculator to see how quickly you would die if left uncovered outside.)
6. You can make snow with a pot of boiling water.