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The NWS Wind Chill Temperature (WCT) index uses advances in science, technology, and computer modeling to provide an accurate, understandable, and useful formula for calculating the dangers from winter winds and freezing temperatures. The index does the following:

  • Calculates wind speed at an average height of 5 feet, the typical height of an adult human face, based on readings from the national standard height of 33 feet, typical height of an anemometer
  • Is based on a human face model
  • Incorporates heat transfer theory based on heat loss from the body to its surroundings, during cold and breezy/windy days
  • Lowers the calm wind threshold to 3 mph
  • Uses a consistent standard for skin tissue resistance
  • Assumes no impact from the sun, i.e., clear night sky.

Wind Chill Chart: Color Chart in PDF, Black and White, Knots, High Resolution TIF

Have more questions? Check our Frequently Asked Wind Chill Questions, Terms and Definitions page and download our free wind chill brochure.

Wind Chill Calculator:

Air Temperature  
Wind Speed 

Wind Chill Temperature:

Wind Chill Temperature is only defined for temperatures at or below 50°F and wind speeds above 3 mph. Bright sunshine may increase the wind chill temperature by 10°F to 18°F.