what is wind-chill?

Answer 1

The relative decrease in temperature caused by the wind.

Wind is one method of cooling, it improves evaporation and it removes the warm air around us. When the temperature is really cold wind makes it feel like it is colder.

According to Wikipedia: http://en.wikipedia.org/wiki/Wind_chill
"Wind chill is the apparent temperature felt on exposed skin due to the combination of air temperature and wind speed. Except at higher temperatures, where wind chill is considered less important, the wind chill temperature (often popularly called the "wind chill factor") is always lower than the air temperature. In cases where the apparent temperature is higher than the air temperature, the Heat Index (HI) is used instead."

See the chart that is with the article to calculate it.

The opposite of Wind Chill is the heat index (http://en.wikipedia.org/wiki/Heat_Index). As the temperature increases the humidity has a stronger effect on how hot it feels to you.

Answer 2

It is an artificial "equivalent temperature" that tries to take into account the cooling factor of wind plus temperature. The combination of the wind with a given temperature will cool a object or person at a rate the wind chill temperature.

The media love it since that temperature says it is colder than the air temperature. It has no meteorological significance.

Water with an air temperature of 33 degrees F with a wind chill temperature of 22 degrees F will never freeze.

Answer 3

Wind chill is what your body actually feels outside because of the wind.

Say it's 30 degrees outside, but the wind chill makes it 20, your body will feel like it's 20 even though it's 30.

Answer 4

Wind chill is a derived effect of wind and temperature on the human body. Simply, if you are outside when it is cool, and there is a wind, you will feel colder than it actually is.