Wind Chill Index by National Weather Service
 

There have been many wind chill index models but I found this one.

http://www.nws.noaa.gov/om/windchill/

Quit reminding us that Winter is almost here!

Let's see......went for a short ride this evening. Temp 30F and averaged 15mph. Yep.....felt like about 19F. Cold fingers.

I have friends all over the USA and use this one.


http://vortex.plymouth.edu/uschill.gif

you guys factor in your bike speed too?

If the air is calm, then your speed is the wind speed.

So, if it's 35F out and with the wind chill it feels like 25F (that's like -4C), will puddles freeze???

no

I don't pay any attention to the alleged wind-chill factor. I make my own as I ride anyway, and how do they know how fast or in what direction relative to the wind that I'm going?

I think it's all more crap for them to get themselves worked up into a lather over anyway. Any day now I expect to hear on The Hyperbole Channel something like, "OMG a snowflake! We're all gonna die!"

Wind chill and heat index never have made much sense to me.

The idea with wind chill is that you lose more heat when the wind is blowing than when it it's not. The problem is that there's no way to correlate the two. If you generated wind chill tables based on Person A wearing one set of clothes, that would be different from Person B wearing a different set. So all it really tells you is that "cold and windy" feels colder than just "cold". And you don't need a table to know that.

As best I can tell, the sole reason for the existence of wind chill and heat index is that it sounds more impressive on the news. That's why you never hear them say, "It's going to be 75 today, but the wind will make it feel like 70" or "It will be 75 today, but the heat index will make it feel like 70" or "It will be 100 degrees today, but the wind chill will be 85".

Yeah, windchill is meaningless to me as well. This whole "Feels like..." is silly.

Adam

I used to do a lot of Mountain biking and hate to say it but wind chill is something you have to take into account at this time of year. Riding on the low lands in cold or freezing weather and you have to be properly dressed for the weather. A 20mph wind will take body heat away from you providing you have enough layers on it will not bother you too much except on the extremities.

Now climb a 15% hill for a mile in a well protected gully or lea of the hill and you will be working. Body will get warm and a bit of unzipping will take place. Get to the top of that hill and hit the 40mph wind on a sweaty body and you will notice the wind chill factor. Especially if you have to stand around a bit to recover or wait for the rest of your group.

I learnt the hard way and I now carry in my back pocket a Pertex jacket on all rides at this time of year. Weighs nothing- packs down small and looks as though it will do nothing to keep you warm. It has no warming qualities to it and most definitely is not waterproof but Pertex is completely windproof. Put that on when the wind starts taking your body temp away and the wind will not have an effect on you.

I have even noticed it in the last week over here. Had freezing temps in the mornings and at the start of the week had a bit of wind at 30F. It was cold. Later in the week it was colder but no wind. Definitely felt a lot warmer.

good info - sounds like how my Dad prepped us for hiking in all conditions.

one of my recent mental questions has been what would happen if I got a flat and had to do a field repair. I mean I'm dressed perfectly for riding but not for sitting for 15 minutes.