(WTNH) — We often hear the terms “wind chill” and “wind chill factor,” but what is wind chill?
Wind chill is defined as “The apparent temperature felt on the exposed human body owing to the combination of temperature and wind speed.”
Before we get into how “Wind Chill” is calculated, let’s talk about how cold it’s going to get this weekend with the wind chill!
The forecast for this afternoon features temperatures in the 30s but the wind chill temps will be in the 20s.
Overnight tonight temps drop down into the teens but the winds start to pick up and it will feel like below 0°F to low single digits.
Saturday afternoon winds increase even more, actual temps will be in the 20s but wind chill just above 0°F
But here’s a breakdown of what wind chill is and how to calculate it!
- Calculates wind speed at an average height of 5 feet, the typical height of an adult human face, based on readings from the national standard height of 33 feet, typical height of an anemometer
- Is based on a human face model
- Incorporates heat transfer theory: heat loss from the body to its surroundings, during cold and breezy/windy days
- Lowers the calm wind threshold to 3 mph
- Uses a consistent standard for skin tissue resistance
- Assumes no impact from the sun, i.e., clear night sky
The new formula for winds in mph and Fahrenheit temperatures is:
Wind chill temperature = 35.74 + 0.6215T – 35.75V (**0.16) + 0.4275TV(**0.16)
In the formula, V is in the wind speed in statute miles per hour, and T is the temperature in degrees Fahrenheit.
Note: In the formula, ** means the following term is an exponent (i.e. 10**(0.5 ) means 10 to the 0.5 power, or the square root of V), – means to subtract, + means to add. A letter next to a number means to multiply that quantity represented by the letter by the number. The standard rules of algebra apply.
Luckily anyone can now calculate the wind chill with a chart like these listed below. Stay warm out there!
Meteorologist Kevin Arnone