All right. Here are the voices of some meteorologists around the country. This was in Indianapolis.
UNIDENTIFIED MAN: This is the coldest wind chill I've ever reported in on the Weather Channel. It's 41 below zero. The air temperature is 13. In fact, it has dropped eight degrees in four hours this morning, as that wind just eats right through you.
GREENE: And no surprise, it is also cold in Green Bay, Wisconsin.
And with much of the nation is in the middle of this brutal cold snap, let's take a moment to hear from scientists who study other planets or even the chilliest places on Earth. Those researchers commonly encounter temperatures that make this news-making cold seem downright balmy. We asked NPR science correspondent Geoff Brumfiel to find out just how low it can go.
GEOFF BRUMFIEL, BYLINE: I caught up with researcher Paul Mayewski yesterday just as he was headed out of town.
A bone chilling cold snap will affect nearly 200 million people in the United States before it subsides. Many areas of the country have wind chill warnings or advisories in place. The cold is sweeping today, east and even south. The Midwest has been frozen now for a couple days. Here's NPR's Cheryl Corley.
CHERYL CORLEY, BYLINE: Walk down a Chicago street and you might not even recognize your best friend. The frigid temperatures mean just about everybody is bundled - scarves drawn tight, hats pulled down low, often only eyes visible.