It's freezing cold in the Chicago area on Tuesday but it's not record-breaking. The lowest temperature recorded on Jan. 22 was 17 degrees below zero in 1937 -- without the wind chill.
What does wind chill mean? It's the temperature it "feels" like when exposed to skin, and today that means between -10 and -20.
Here's how it works. Your body produces heat, and the wind can whisk away that heat, replacing it with colder air and making the temperature feel much colder.
It also increases the chance for frostbite. In 5-degree temperatures, it only takes about 30 minutes for frost bite to set in.
Because Chicago temperatures will hover between 1 and 8 degrees in the morning, you are encouraged to layer on loose-fitting clothing to keep in the warmth. Since wind chill affects exposed skin, wrap a scarf around your face to protect it.
Chicago could see wind chill values well below zero again overnight. Temperatures moderate Wednesday afternoon to the low 20s.