How Is Wind Chill Calculated? (Plus 9 More Wind Chill FAQs)

Windchill factor is only for humans. If the wind is blowing 35 MPH, and the temperature is 35 degrees Fahrenheit, the windchill is 20.78. Water does not freeze, but you and I do. Take away the wind and it feels like 35 degrees F.

P E Bobimm

You must never had a water pipe to freeze from a vent not being closed letting wind blow over it. Yes I know 35 deg F is above freezing. I'm not saying it would freeze with that. Just keeping the draft off the pipes they can withstand lower temps before freezing.

How do i know? I'm living in a travel trailer this winter. I have 25ft drinking safe hose with heat tape with insulation over it with about 12ft of uninsulated hose connected to reach the 2ft I was short to the water faucet. All the extra hose is coiled in the hole with the faucet and covered the 2ft out of the hole has insulation only. We have had 4 days below freezing so far with 10 more days forecast. We will see if makes it or not.

Charles

Your pipes do not freeze when you block the draft because you slow the heat loss. The heat tape on the rest of the pipes is introducing heat that keeps the pipes from freezing. Whe the pipes are exposed to the draft or wind the heat loss occurs much faster. If you lose heat faster than you add heat the pipes will cool and visa versa.

Wind Chill is the result of heat being remove more rapidly so it makes you feel colder. Wind will also makes your heating bill go up because your house will also loose heat faster but the outside surfaces will not get colder than the ouside air temperature.

So wind specifically makes humans and other animals feel colder by remove their body heat from their skin surface faster than still air does. It will also cool ojects to the ambient air temperature faster than still air does.

Wind chill specifically describes the the temperature of still air that feels the same as the moving air does on the typical humans skin surface. You must keep in mind that our bodies are constantly heating our skin from within and the air is removing that heat. Moving air removes it faster.

"Wind Chill" is the combined effect of the actual temperature and the wind speed that increases heat loss, and there is the evaporation effect.

NOAA Calc

Wind chill = air temp +wind speed +(air temp)(wind speed) 0.4275

Check www.srh.noaa.gov

10. How is the Windchill is calculated?

The wind chill temperature is calculated using the following formula:

Windchill (ºF) = 35.74 + 0.6215(T) - 35.75(V^0.16) + 0.4275(T)(V^0.16)

Where: T = Air Temperature (F)
V = Wind Speed (mph)
^ = raised to a power (exponential)

Windchill Temperature is only defined for temperatures at or below 50 degrees F and wind speeds above 3 mph. Bright sunshine may increase the wind chill temperature by 10 to 18 degrees F.