Such a wind is often described as a 'lazy' wind, as it does not appear to go around you, but straight through you instead! In such conditions weather forecasters often mention "the wind-chill". But what is it?
Wind-chill is a measure of the amount of heat lost from the skin as the wind blows across it.
Early wind-chill development was based on conditions likely to be encountered in Antarctica. Frostbite is a major hazard to anyone working in such areas. It was found that wind speed was critical to formation of frostbite; whilst it was possible to work in temperatures below minus 40 Celsius, winds of as little as three or four knots can make a dramatic difference.
So in calm air a temperature of 0 Celsius feels like 0 Celsius. But if there is a wind of ten knots blowing it will feel the same as minus five Celsius feels in calm air. As the wind increases to 25 knots, the wind-chill falls to minus 12 Celsius. A wind of 40 knots gives a wind-chill of minus 16 Celsius.
If you feel compelled to find out more, please go to this BBC website on weather. Otherwise just warm up with a nice cup of tea and wrap up warmly!
