GRAND RAPIDS, Mich. (WOOD) — Wind frequently impacts the way our temperatures feel in Michigan. The colder the initial temperature or the faster the wind, the lower the wind chill value will go. Wind chill can be dangerous at times. In fact, a colder wind chill can lead to faster onset of conditions like frostbite or hypothermia.

What is wind chill?

Wind chill is how cold the air will feel as an equation based on actual temperature and wind speed.

Wind chill = 35.74 + 0.6215T – 35.75 (V^0.16) + 0.4275T (V^0.16)

  • T = Temperature in degrees Fahrenheit
  • V = Wind velocity in miles per hour

If you like, you can use this cool wind chill calculator based on what you are seeing at home.

All human bodies emit heat. Usually, that heat stays close to our skin, keeping us warm. On windy days, this bubble of heat is carried away more quickly making it feel colder outside than it actually is.

Wind chill values can plummet to drastic lows, but the equation and table is based purely on how it interacts with human body temperatures.

Does wind chill affect rain or snow?

Because rain and snow do not have a bubble of heat around them, they are not impacted by wind chill. This means the answer to our viewer question this week is “no.” We can see real-time evidence of this on radar this evening. Widespread rain is rolling through the Great Lakes.

Even with wind chills in the 20s, there are various locations that are still reporting steady rain on storm track live.

There is one case where an incoming wind can convert rain to snow, however. A dry wind.

When rain is falling, it typically is in a nearly saturated environment. However, if wind is blowing into the environment that is drier, it can trigger a cool effect. Literally!

As dry wind hits falling rain drops it leads to evaporation. Evaporation causes cooling.

We experience this evaporative cooling phenomenon any time we get out of shower and feel cold. Sometimes if the incoming dry air is cold enough, it will drop the air temperature below freezing. We see this in Michigan at times when a cold east wind slowly converts rain into freezing rain, then sleet, and finally to snow.