The wind chill factor

This Wind Chill Chart is provided to help determine how cold you will feel on a motorcycle even in warm temperatures with a slight breeze. The wind chill factor is a measure of how fast heat is being removed from your body. For example, if the air temperature is 4 degrees celsius and you are riding at 32 kph, it feels the same as 1 degrees celsius with no speed at all.

The National Weather Service chart below is supposedly a “new” formula…..

The current formula uses advances in science, technology, and computer modeling to provide a more accurate, understandable, and useful formula for calculating the dangers from winter winds and freezing temperatures. Specifically, the new WCT index:

  • Calculates wind speed at an average height of 5′ (typical height of an adult human face) based on readings from the nationnal standard height of 33 feet
    (typical height of an anemometer)
  • Is based on a human face model
  • Incorporates modern heat transfer theory (heat loss from the body to its surroundings, during cold and breezy/windy days)
  • Lowers the calm wind threshold to 5 kph
  • Uses a consistent standard for skin tissue resistance
  • Assumes no impact from the sun (i.e., clear night sky)

Note: Windchill Temperature is only defined for temperatures at or below 10 degrees C and wind speeds above 5 kph. For more information, or to calculate windchills.

 

NWS-windchill chart-OPT

You can see from the above chart that proper clothing is essential for safety and comfort while cruising down the highway. (Note: Winds above 65 kph have little additional effect.