If the forecast called for 1K (1 Kelvin) with 20mph gusts of wind, would the wind chill be below 0K? “Wind chill” is a very ad hoc, artificial measure used to describe the fact that cold air pulls heat out of us faster when it’s moving. When air is stagnant and you’re standing still, you’ll be surrounded by a bubble of warm air (heated by body heat). When the wind is blowing however, that layer of warm air is pushed away and we’re exposed to the actual air temperature. Wind chill is pretty subjective (people of different sizes and shapes will experience wind chill differently), and not terribly exact, but the standard gives you a decent ball park estimate.