When preparing to go outside in the winter, it isn't the temperature you listen for on the radio, it's the temperature with the wind chill. While expressed in temperature units (degrees Celsius in Canada) wind chill is not a temperature, it is measure of the "feels-like" sensation on human skin when wind is combined with an already cold temperature. Click here to go the Environment Canada’s Wind Chill Calculator.     How does wind chill work? The area around our skin that our bodies heat is called the boundary layer. This layer helps to protect us from the surrounding temperatures. When a wind occurs, it blows this boundary layer away, causing our bodies to work harder to restore our natural insulation. The elimination of this layer exposes our bodies to the cooler surrounding air, therefore causing our skin temperature to drop.     How does wind chill affect me? Wind chill can be very dangerous because it increases the rate at which our bodies cool. Frostbite, hypothermia and over-exposure to the cold are all serious threats caused by wind chill. Make sure to take the proper precautions such wearing protective clothing and decreasing time spent outside when wind chill is a factor. Remember - skin normally begins to freeze at -25 and will freeze very quickly at wind chills below -35. Also, the wind chill cannot be judged by simply look out the window. A winter day can be clear and sunny also dangerously cold. 26 February 2005: the temperature was -10, but the wind chill made it feel like approximately -18.