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 tissue under it freezes, which can happen much more quickly than you might imagine.
Cold and wind chill
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 affect 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 was zero degrees Fahrenheit and calm, your chance of frostbite is relatively low. Add wind at 15 miles per hour, and it would take only 30 minutes before frostbite sets in. If the wind rose over 50 mph, 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 degree weather with a wind speed of just over 25 mph.