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Semper_Fi
12-17-2009, 02:39 PM
Road yesterday and it was brisk, comfortable but brisk.

Anyway found this link for Calculating Windchill Value (http://ridemyown.com/windchill.shtml)

Did not know there was an old and new value for windchill, all i knew was that is was quite cold if I lifted my face shield :lurk

henzilla
12-17-2009, 02:45 PM
Cool...so to speak!

pretty big difference between the two. I figure it's bad on days my heated gear feels like it's off once I start rolling:laugh

BUBBAZANETTI
12-17-2009, 02:55 PM
Good to know, haven't been much of a Rounder since moving to NYC, but it does give me good appreciation of my 19 degree ride 300 miles from central ma to central ny...............without a heated jacket.

AZ-J
12-17-2009, 04:12 PM
This one (http://www.easysurf.cc/cnver16.htm) does Windchill and Heat Index. We need the latter as late Spring, Summer, and early Fall comes.

XTrooper
12-17-2009, 11:07 PM
I'd rather not know.

"Ignorance is bliss!" :laugh

Semper_Fi
12-17-2009, 11:26 PM
I'd rather not know.

"Ignorance is bliss!" :laugh


Good point!

terham
12-17-2009, 11:57 PM
I prefer the new wind chill index over the old index. It makes you think it's not as bad as you think it is.:laugh

Ken F
12-18-2009, 12:45 AM
........I have a lot easier time believing the old one however.

r11rs94
12-18-2009, 12:54 AM
Does this take into account if its a "DRY COLD". :laugh

Semper_Fi
12-18-2009, 01:11 AM
Does this take into account if its a "DRY COLD". :laugh


Don't laugh i was walking my dogs this morning in the "dry" cold and I had tears running as the wind was ripping thru me, even the dogs weren't too happy.

On a side note any body know why we have the old and new Wind chills.....

Requiring minds want to know :lurk

angysdad
12-18-2009, 02:07 AM
One thing to note...above approx 40mph, friction plays a major role in wind chill values. Very little difference between say, 45 or 70mph. So if you are cold, drive faster. You will not be any warmer, but you will get there sooner. This is not particularly good advice if you have frozen hands, etc. If you are too cold, stop and stay safe!

Ken F
12-18-2009, 02:25 AM
>On a side note any body know why we have the old and new Wind chills.....<

As copied from directly below the first posted wind chill calculator:

Specifically, the new WCT index will: use wind speed calculated at the average height (5 feet) of the human body's face instead of 33 feet (the standard anemometer height); be based on a human face model; incorporate modern heat transfer theory (heat loss from the body to its surroundings, during cold and breezy/windy days); lower the calm wind threshold to 3 mph; use a consistent standard for skin tissue resistance; and assume the worst case scenario for solar radiation (clear night sky).

460

Semper_Fi
12-18-2009, 12:03 PM
One thing to note...above approx 40mph, friction plays a major role in wind chill values. Very little difference between say, 45 or 70mph. So if you are cold, drive faster. You will not be any warmer, but you will get there sooner. This is not particularly good advice if you have frozen hands, etc. If you are too cold, stop and stay safe!

When my wife get's cold - hang on, luckily I have a GT to keep up with her R in these situations!!:thumb

Semper_Fi
12-18-2009, 12:03 PM
>On a side note any body know why we have the old and new Wind chills.....<

As copied from directly below the first posted wind chill calculator:

Specifically, the new WCT index will: use wind speed calculated at the average height (5 feet) of the human body's face instead of 33 feet (the standard anemometer height); be based on a human face model; incorporate modern heat transfer theory (heat loss from the body to its surroundings, during cold and breezy/windy days); lower the calm wind threshold to 3 mph; use a consistent standard for skin tissue resistance; and assume the worst case scenario for solar radiation (clear night sky).

460


I just saw the calculator - never read the web page.

Another one for RTFM!

mika
12-18-2009, 03:55 PM
As 460 explained it is definitions of how to calculate the table. Another explanation for the change is given by Wikipedia (http://en.wikipedia.org/wiki/Wind_chill). At first it was defined as the temperature at which the wind chill index would eb the same in the complete absence of wind. Later it was redefined from the absence of wind to a air speed of 4mph, the lowest wind speed a cup anemometer could measure at the time. I have seen other explanations as well.

Sometimes cold is just cold no matter how windy you get. ;)

Semper_Fi
12-18-2009, 03:58 PM
Sometimes cold is just cold no matter how windy you get. ;)

Word

widebmw
12-18-2009, 04:26 PM
Word

Windbreaker. :laugh

AZ-J
12-19-2009, 02:20 AM
Word

Warmth

It was 70 here today, and 64 F now @ 7:20 PM. Walk after dinner time.

Semper_Fi
12-19-2009, 02:29 AM
15 degrees with a shallow wind 2129

Brandy on the couch

saddleman
12-25-2009, 08:09 PM
As far as I can remember the wind chill factor only effects exposed skin. My skin is never exposed when I ride. Winter or summer.

AZ-J
12-25-2009, 08:46 PM
saddleman, I agree, but leaks allow wind chill to do awful things, even to covered skin. This Rule does not apply to heat index, however, as a 103 dry day, that feels like 98 or 99, still feels like 103 or more, in gear, and/or on a hot bike.

I am glad my S bike is not a hot bike, since it hold little heat. I still won't ride w/o some gear, mesh for shorter day rides, and vented for longer.