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Weather Software => Virtual Weather Station => Topic started by: geno on February 11, 2012, 12:34:34 PM
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It's finally cold in Atlanta and the wind is really kicking up. I checked my weather station to see what the wind chill was and the program shows the ambient temp and wind chill as the same. Wind of 12 mph should make a difference. Since this calculation is being done inside the program (I think) what might be the problem?
Thanks,
-gene
www.genesweather.info
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Appears to be working from what I can tell. I see a temp of 36.4 and a Wind Chill of 35.8 with the wind at 2mph. That sounds reasonable to me.
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Thanks for the reply. What I discovered is that there is a new calculation for computing wind chill. And, if the wind speed is relatively low, it will have little or no impact on the wind chill reading. Do a Google search for wind chill calculator to obtain the new formula. I put both in an Excel spreadsheet to see the difference using the same parameters.
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Thanks for the reply. What I discovered is that there is a new calculation for computing wind chill. And, if the wind speed is relatively low, it will have little or no impact on the wind chill reading. Do a Google search for wind chill calculator to obtain the new formula. I put both in an Excel spreadsheet to see the difference using the same parameters.
Yes, NWS began using a new Wind Chill calculation in November 1, 2001. A link to their website that includes a built-in Wind Chill calculator is as follows:
- http://www.nws.noaa.gov/om/windchill/ (http://www.nws.noaa.gov/om/windchill/)
NOTE: The wind chill formula is only good when the wind is above 3mph and below 110mph.
Also, wind chill is only valid for temperatures of 40 degrees F and below.
UPDATED: 2/12/2012@ 4:25pm PT
Here is another link that shows both Wind Chill and Heat Index which is based on Temp and Rel Humidity:
- http://www.erh.noaa.gov/er/iln/tables.htm (http://www.erh.noaa.gov/er/iln/tables.htm)
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50F(10C) is the cut off, not 40F
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50F(10C) is the cut off, not 40F
Oops, that was a typo. To be fully accurate the temp range has to be above -50F and less than +50F.