Explaining wind chill and how it is calculated

SIOUX FALLS, S.D. (Dakota News Now) - The term ‘wind chill’ is all too common in our area from roughly November through March, but what exactly is it and how is it calculated?

The wind chill is a term used to explain what it feels like to the skin.

Our bodies lose heat through convection, but if there is very little to no wind, then that layer of heat will remain around us and help us stay warmer. However, if we have a strong wind, the wind will break up that warm layer and that leads to the heat loss speeding up and thus making it feel much colder.

The two things that make up the wind chill is the wind and the air temperature.

Something that people may not know is that the temperature and the strength of the wind and greatly impact the wind chill.

Let’s take a look at a few examples.

If the temperature is 5 degrees and the wind is 10 mph, this means the wind chill would be -10 degrees. If you increase the wind to 20 mph, then the wind chill would drop to -15 degrees.

Let’s say we increase the temperature to 30 degrees. If the wind is 5 mph, the wind chill would be 25 degrees. If we increase the wind to 20 mph, the wind chill would drop to 17 degrees.

Finally, let’s drop the temperature to -15 degrees. If the wind is 10 mph, the wind chill would be -28 degrees. If the wind is increased to 20 mph, the wind chill would drop to -42 degrees.

The equation below shows how the wind chill is calculated.

35.74+0.6215(Air Temperature) – 35.75(Wind Speed^0.16) + 0.4275(Air Temperature)(Wind Speed^0.16)

You can also see the chart below to determine what the wind chill would be at different temperatures and wind speeds.