What Is Meant by Wind Chill?

Wind chill is an estimate of how cold the wind makes a person feel in cold weather. The faster the wind blows, the quicker the body loses heat. Therefore, the feeling of cold increases as the speed of the wind increases.

For example, if the temperature outdoors is 30 degrees Fahrenheit, and the wind is blowing at a speed of 10 mph, people lose as much body heat and feel as cold as if the temperature were 10 degrees Fahrenheit and the wind calm.

The wind chill temperature gives us a more accurate idea of how cold it is than just a thermometer reading alone. However there is still no universally agreed formula for wind chill. It is not an exact science and depends on what you want to measure.

One of the first measures, known as Siple-Passel, was based on observing how quickly bottles of water froze in the Antarctic wind.

Later indices attempted to apply it to human physiology. Humans were tested naked in wind tunnels to assess the impact on temperature. The height used for measuring the wind was 10 m – far above street level.

How is wind chill calculated? Wind increases the rate at which a body loses heat, so the air on a windy day feels cooler than the temperature indicated by a thermometer.

This heat loss can be calculated for various combinations of wind speed and air temperature and then converted to a equivalent temperature (or wind chill factor).

Content for this question contributed by Sheri Johnson, resident of Taunton, Bristol County, Massachusetts, USA