What is Wind Chill Calculator?
The National Weather Service (NWS) Wind Chill temperature index measures the accelerated rate of body heat loss caused by wind combining with sub-freezing cold air.
How to Use This Calculator
- Enter air temperature in °F (50°F or lower).
- Enter sustained wind speed in mph.
- Review apparent temperature feel and frostbite risk.
The Mathematical Formula & Variables
Wind Chill (°F) = 35.74 + 0.6215*T - 35.75*(V^0.16) + 0.4275*T*(V^0.16)
Step-by-Step Worked Example
Scenario: 25°F air temperature with a 20 mph wind.
- Plug into NWS formula: 35.74 + (0.6215 * 25) - (35.75 * 20^0.16) + (0.4275 * 25 * 20^0.16).
- Resulting wind chill temperature = 9.0°F.
Result: Wind Chill: 9.0°F
Frequently Asked Questions
At what wind chill temperature does frostbite occur in under 30 minutes?
When the wind chill index falls to -18°F (-28°C) or colder, frostbite on exposed skin can occur within 30 minutes or less.