FARGO, N.D. (Valley News Live) -- If you plan on being outside in the double digit below zero temperatures, bundle up, because frostbite happens quickly.
Experts at F-M Ambulance say you should worry when you stop shivering, that's a sign of hypothermia.
Frostbite happens when you have a tingling sensation in your fingers, and it turns to a waxy feeling.
"Make sure your kids are fully covered from head to toe," said Don Martin, Communications Manager of F-M Ambulance. "With kids, it's so easy, they get hot, they start taking layers off, or they leave their mittens. You have to start making sure that they have to be protected, or maybe you have to go pick up your children to ensure that they go from the building to the car very quickly."
If you have a severe form of frostbite, aggressive re-warming can be detrimental to your health.