Frostbite can strike quickly. Here's what you need to know

It's COLD. We're talking dangerous cold. Cold that might rob you of the tips of your nose, ears, chin, fingers or toes if you're not careful. Called frostbite, it happens when the skin and the tissue under the skin freezes, which can happen much more quickly than you might imagine.

Frostbite is not only dependent on the outside temperature. It's also affected by the wind chill factor. As the speed of the wind increases, our bodies cool at a faster rate, causing the skin temperature to drop. Higher altitudes can also increase the speed at which skin can freeze.

The National Weather Service has created a wind chill chart that shows the time it might take to develop frostbite at varying temperatures and wind speed. The index was tested on human face models.

For example, if it were zero degrees Fahrenheit (minus 17.8 degrees Celsius) and calm, your chance of frostbite would be relatively low. Add wind at 15 miles per hour, and it would take 30 minutes before frostbite set in. If the wind rose to over 50 miles per hour, it would take a mere 10 minutes for frost to bite.

Your skin would freeze in a scant five minutes if you were out in minus 25 degrees Fahrenheit (minus 31.7 degrees Celsius) with a wind speed of just over 25 miles per hour.

You are more susceptible to frostbite if you smoke, take medications called beta-blockers, have poor blood supply to the legs, or have diabetes or Raynaud syndrome, a condition in which strong emotions or cold temperatures cause blood vessels to spasm and block blood flow to extremities.

Older people and people who live outside without proper clothing, heating and food are also at high risk, as are hikers and hunters who aren't properly clothed and stay outdoors too long.