CHART: Here's How Long You Can Stay Outside In Extreme Cold Before Getting Frostbite

After early January's "polar vortex," the second cold snap is upon us. A storm could hit the Northeast Tuesday, bringing huge amounts of snowfall and bitter temperatures. Straight temperatures aren't all that matter. Brave adventurers (or those forced to leave their homes) should really consider wind chill — the temperature it "feels like" outside based on the rate of heat loss from exposed skin, according to the National Weather Service. In colder temperatures, you shiver to produce heat in y...