The Wind Chill Calculator finds how cold it feels on exposed skin from the air temperature and wind speed, using the U.S. National Weather Service formula.
Wind chill: -6.6 °F = -21.4 °C
| Wind chill | -6.6 °F = -21.4 °C |
| Frostbite risk | Low frostbite risk |
Wind removes the thin layer of warm air around your body, so you lose heat faster and feel colder than the thermometer shows. Wind chill expresses this as an equivalent temperature on calm days. It applies only to people and animals, not to objects or car engines.
Wind chill (°F) = 35.74 + 0.6215T − 35.75V^0.16 + 0.4275T × V^0.16, with T in °F and V in mph. It is valid for T ≤ 50 °F and V ≥ 3 mph.
Worked example (defaults): 10 °F with a 15 mph wind feels like −6.6 °F (−21.4 °C).
At wind chills below about −18 °F (−28 °C), frostbite can occur on exposed skin within 30 minutes; below −35 °F, within 10 minutes. Dress in layers, cover your head, face and hands, and stay dry.
Can wind chill make water freeze above 32 °F? No, objects cannot cool below the air temperature.
Why does the formula use 5 ft height? Wind is measured at 33 ft and adjusted to face height.
What about hot days? Use the Heat Index Calculator.