Wind Chill Chart

[BMWRider]

found this on the f650.com.....i found it very interesting especially for those who are out and about riding still (luck bastards)

[WINTER1100S]

Looks like my last ride "felt like" 25 below! and I don't mean last last ride, if it ever clears up here I'm sure I'll venture out (on dry roads) to see what it "feels like"!

[repoe3]

i would like to see the relative wind chill at 55+ MPH.

repoe3

[BMW Atlanta]

55? yeah right, how about 75-80 mph???

[repoe3]

that is what i am talking about, the figures from 55 and up...

repoe3

[dannyleo]

Windchill
The National Weather Service (NWS) will implement a new Wind Chill Temperature (WCT) index for the 2001/2002 winter season. The reason for the change is to improve upon the current index used by the NWS and the Meteorological Services of Canada (MSC) which is based on the 1945 Siple and Passel Index.

For over a year, there has been discussion within the NWS and MSC about updating the WCT. During the Fall of 2000, a special group - consisting of the National Weather Service, MSC and the International Society of Biometeorology - evaluated the existing wind chill formula and made changes to improve upon it. Chaired by the NWS, the group's goal was to internationally upgrade and standardize the Wind Chill Index.

The new Wind Chill/Temperature Index will make use of advances in meteorology, biometeorology and computer modeling to provide a more accurate, useful formula for calculating the dangers from winter winds and freezing temperatures. In addition, clinical trials have been conducted and the results of those trials have been used to verify and improve the accuracy of the new formula.

Led by the NWS, implementation of the standardized WCT Index will take place throughout the nation and will involve the entire meteorological community and the media - which will play an important role in explaining the index to the general public. In this way, an accurate and consistent measure will be provided to help the public protect itself against the dangers of frostbite and hypothermia. The index will be implemented in Canada and the United States in order to have a consistent WCT Index for North America.

Specifically, the new WCT index:

uses calculated wind speed at an average height of five feet (typical height of a human face) based on readings from the national standard height of 33 feet (typical height of an anemometer);
is based on the latest heat transfer theory, i.e., heat loss from the body to its surroundings, during cold and breezy/windy days;
uses a standard factor for skin tissue and assumes a no sunlight scenario
The new equation

Wind Chill (oF) = 35.74 + 0.6215T - 35.75(V0.16) + 0.4275T(V0.16)



Where, T = Air Temperature (oF)
V = Wind Speed (mph)


The Old Equation
Twc = 0.0817(3.71 V 0.5 + 5.81 - 0.25V)(T - 91.4) + 91.4

where

V = wind speed in mph
T = temperature in oF
Twc = windchill
Temperature (F)

If this doesn't work, then check it out at http://www.srh.noaa.gov/jan/wchill.html
This shows both the windchill chart and a graphic comparison of new and old going out to 100mph. My upload of the pic failed.

[dannyleo]

Oh yeah, I didn't write the above, just copied and pasted from that web site.

[Robert Au]

Sydney, AUSTRALIA 20:30.

Care factor 0.00

[WINTER1100S]

Originally posted by dannyleo
Oh yeah, I didn't write the above, just copied and pasted from that web site.

I was gonna say, MAN are you long winded!

[WINTER1100S]

Courtesy of the National Weather Service...

[szentthomas]

If you want to know what the temperture for any given temperture and speed just email me and I will send you an excel worksheet. (I couldn't post it)

I used the new formula from the NWS and put it in excel. All you do is just put in the Velocity (wind) or in our case how fast we ride and put in the Temperture and out comes the calulated Tempature in degrees.


BTW -
repoe3 65 deg@ 55 mph = 53.8 F

bmw atlanta -
60 deg @ 70 mph = 53 F
60 deg @ 80 mph = 52.6 F

My moring commute -
41 deg @ 60 mph = 26 F

Take care - I hope you find this handy