Wind Chill Calculator
Calculate the wind chill factor based on temperature and wind speed using the NWS formula.
A wind chill calculator estimates how cold it feels when wind is factored in, using the NOAA wind chill formula for exposed skin.
Examples
Cold winter day
Dangerous conditions
Frequently Asked Questions
What does wind chill actually measure?
Can wind chill freeze water pipes?
Quick Tips
- •Wind chill only applies when it is 50°F (10°C) or colder with wind speeds of 3+ mph.
- •Dress in layers and cover exposed skin when wind chill drops below 0°F (-18°C).
- •The NWS formula was updated in 2001 based on modern research on heat loss from the human face.
A wind chill calculator estimates how cold it feels when wind is factored in, using the NOAA wind chill formula for exposed skin.
How to Use This Calculator
Select your unit system, enter the air temperature and wind speed. The calculator uses the National Weather Service (NWS) formula to compute the wind chill index and frostbite risk.
Understanding the Formula
NWS Wind Chill Index: WC = 35.74 + 0.6215T - 35.75(V^0.16) + 0.4275T(V^0.16), where T is temperature in °F and V is wind speed in mph. Valid for T <= 50°F and V >= 3 mph.
Examples
Cold winter day
Temperature: 20°F, Wind: 25 mph. Wind Chill = 35.74 + 0.6215(20) - 35.75(25^0.16) + 0.4275(20)(25^0.16) = 6.2°F. Feels 13.8°F colder.
Dangerous conditions
Temperature: 0°F, Wind: 30 mph. Wind Chill = -26.2°F. Frostbite possible in 10 minutes on exposed skin.
Frequently Asked Questions
What does wind chill actually measure?
Wind chill measures how cold it "feels" on exposed skin due to the combined effect of cold air and wind. Wind increases the rate of heat loss from the body, making it feel colder than the actual air temperature.
Can wind chill freeze water pipes?
No. Wind chill affects how quickly an object (or person) cools to the ambient air temperature, but cannot cool anything below the actual air temperature. Pipes freeze based on the actual temperature, not wind chill.
Assumptions & Limitations
- Uses the NOAA 2001 wind chill formula, valid for temperatures at or below 50°F (10°C) and wind speeds above 3 mph.
- Assumes the person is walking at 3.1 mph and exposed skin is in shade.
- Does not account for solar radiation, which can make it feel warmer.