Increased wind speeds accelerate heat loss from exposed skin. No specific rules exist for determining when wind chill becomes dangerous. As a general rule, the threshold for potentially dangerous wind chill conditions is about -20°F.
the cooling effect on the body due to a combination of wind and temperature.
The amount of cooling one "feels" due to the combination of wind and temperature. Wind Chill Chart View an informative QuickTime animation on the wind chill factor. (1.2M)
The apparent temperature which describes the cooling effect on exposed skin by the combination of temperature and wind, expressed as the loss of body heat. Increased wind speed will accelerate the loss of body heat. A wind chill factor of 30 degrees or lower on exposed skin will result in frostbite in a short period of time.
The amount of cooling one "feels" due to the combination of wind and temperature. The formula to calculate wind chill is: WC=35.74+0.6215T-35.75(V**0.16)+0.4275T(V**0.16) where V=wind speed in MPH and T=temperature F. See Wind Chill Chart