See how wind increases perceived cold on exposed skin.
Overview
Wind chill models how wind speed and cold air temperature combine to increase heat loss from exposed skin compared to still air. It is not an actual thermometer reading but a comfort and risk indicator.
North American wind chill index uses a regression formula with temperature in Fahrenheit and wind in mph valid for certain ranges. At very low wind, chill approaches actual temperature; strong wind lowers perceived temperature.
Wind chill does not apply to inanimate objects that do not lose heat biologically; metal still cools to air temperature regardless of “feels like.” Dressing for actual temperature, wind blocking, and minimizing exposed skin remains essential.
Hypothermia and frostbite risks rise as wind chill drops. Monitor forecasts, limit outdoor exposure, and use layered clothing and windproof shells in winter sports and construction.
Steps
Ambient temperature in °F or °C per mode.
Sustained wind at measurement height.
Apply regional formula.
Compare with exposure charts.
Short gusts can worsen chill momentarily.
Adjust clothing and time limits.
Math
WCT = 35.74 + 0.6215T − 35.75V^0.16 + 0.4275TV^0.16 (°F, mph)
Empirical fit to heat transfer models for human skin under wind and cold conditions.
Worked cases
Apply WCT regression
Feels like ≈ 17°F.
Chill approaches actual T
Minimal wind effect.
Large negative chill index
High frostbite risk; limit exposure.
Why use this
Questions