Why Care about the “Wind Chill?”

Scale of approximate "wind chill" given certain conditions

Now that we’re into December, this is a good time to review what “wind chill” is.  During the winter, air temperature isn’t always an accurate measure of how cold you feel outside.  The strength of the wind often acerbates the intensity of the winter cold.

“Wind chill” is the temperature it will actually feel like as the wind blows the heat away from exposed skin.  Consequently, only living things such as people and pets will feel the effects of wind chill.  However, when wintery precipitation is in the forecast, the air temperature is all that matters.  That’s because even if the wind chill is below freezing, water will not freeze if the air temperature is above freezing.

The summer equivalent of “wind chill” is the “heat index.”  The “heat index” is the temperature it actually feels like out when you combine the air temperature with the relative humidity.  As Washingtonians commonly experience during the summer months, the higher the relative humidity is, than the higher the “heat index” will be.  As in the case of “wind chill,” inanimate objects do not feel the “heat index.”