How does the windchill factor work? - HowStuffWorks
Apr 01, 2000 The windchill factor is the same effect that causes you to blow on hot soup to cool it down. The movement of the air increases the soup's loss of heat by convection, so the soup cools down faster. See How Thermoses Work for details on radiation, conduction and convection. For an inanimate object, windchill has an effect if the object is warm.
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