The 2001 National Weather Service formula combines air temperature and wind speed: 35.74 + 0.6215×T − 35.75×V^0.16 + 0.4275×T×V^0.16, where T is temperature in °F and V is wind in mph. The 0.16 exponent reflects how wind speed (rather than linearly) affects heat loss. Valid for temperatures below 50°F and winds of 3+ mph.
Wind chill measures how fast wind removes heat from exposed skin. Still air at 10°F feels less harsh than windy 10°F, because wind accelerates heat loss. Wind chill is not a real temperature but an "apparent temperature" or "feels-like" value.
The current wind chill formula was adopted in 2001, replacing the 1945 formula. The update reflected improved science on how wind actually affects human skin cooling.
No. Wind chill only applies to living organisms with metabolic heat. Objects cool toward the actual air temperature regardless of wind chill. Wind does accelerate object cooling but is separate from "wind chill."
Frostbite exposure times come from medical research and NWS charts. Risk depends on wind chill, duration, and individual factors (age, clothing, health). The times are conservative estimates for unprotected skin.
"Feels like" can include humidity, solar radiation, and other factors beyond wind chill. Wind chill focuses specifically on wind-driven heat loss from skin.
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.