wind chill factor

CARTEEUSMC · Post by **CARTEEUSMC** » Sat Dec 02, 2006 4:31 am

Was wondering while riding below 26 degrees, what was the real temperatue when riding. Here is a link, just in case anyone else was curious like me!

http://observe.arc.nasa.gov/nasa/earth/ ... cript.html

I hope I am not the only one!

MIXR · Post by **MIXR** » Sun Dec 03, 2006 11:10 pm

And on the eighth day God created heated vests, heated grips, thermo-lined gloves, silk balaclavas and insul-socks. What wind-chill?

R4R&R · Post by **R4R&R** » Mon Dec 04, 2006 9:32 am

I've never really counted windchill while riding a bike, because you ALWAYS have wind that is your speed. Windchill only affects 'exposed skin', where it's only a feeling of being colder while the temp is really the same. If the temp is 28, and the windchill is making it seem like 5, then why does the thermometer still read 28? Because the REAL temperature is 28!

Hopefully if you are riding a motorcycle (or even a bicycle) you are covered up with good insulating material and have no exposed 'skin'.

I hope that comes out the way I'm thinking it.

Here is an article explaining it.

Post by **rdsmith3** » Mon Dec 04, 2006 10:22 am

I agree that wind chill is often used incorrectly, especially by TV weather people. They love the drama of saying that the wind chill is 20 below.

OTOH, on a naked bike, there is some loss of heat. Our gear is not perfectly wind proof. The faster I go, the greater the loss of heat. My own personal experience is that if I am going 70 mph on the highway and it is 30 deg outside, I am a lot colder than if I am going 35 mph at the same temperature.

Post by **yjleesvrr** » Mon Dec 04, 2006 10:40 am

There is a temperature gradient in the air near the skin, along with humidity resulting from the evaporation of water from the skin. When wind sweeps this layer of air away constantly, this accelerates not only the evaporation of water from the skin (a conductive process) but also the convective process of heat drawn from the skin directly to the moving air surrounding the skin. It is thus important not only to have covering in layers of clothing but also that the layers are "windproof" to a reasonable extent, i.e. - the air inside the clothing is not removed at too high a rate that drives the convective effect.

The convective effect is what brings the skin near the temperature of the air, and the conductive effect from evaporation can actually draw the temperature of the skin below that of the air!

Post by **NoRRmad** » Mon Dec 04, 2006 2:40 pm

Even with a completely airtight covering, the effect of wind remains, though reduced. At a standstill, a thin layer of warm air will surround the body, heated by radiated energy, and heat conducted through the material of the clothing. As the windspeed rises, this layer is stripped away, leaving colder air in contact with the outer covering, increasing conductive heat loss.

Post by **rdsmith3** » Mon Dec 04, 2006 3:38 pm

the conductive effect from evaporation can actually draw the temperature of the skin below that of the air!

Isn't this why I always feel cold when I first step out of the shower, regardless of how warm the room is?

Post by **yjleesvrr** » Mon Dec 04, 2006 3:39 pm

rdsmith3 wrote:
the conductive effect from evaporation can actually draw the temperature of the skin below that of the air!
Isn't this why I always feel cold when I first step out of the shower, regardless of how warm the room is?

Yup.