Heat Index calculation wrong?

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MeteoTwischkamp
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Heat Index calculation wrong?

Post by MeteoTwischkamp » Wed Sep 13, 2017 1:14 pm

Hi,

I noticed in the current conditions block, that the calculation of the heat index seems to be wrong- currently the temperature is 14.2°C with a humidity of 73%. The apparent temperature looks correct -there's a storm here going on at present, so it definately feels like its below 10°C. However the heat index does look right at least to my layman's eyes- it shows currently 26.8°C. See the attached screenshot.

I tried to find a calculator for the heat index and entered these values however this would be a heat index of 14°C.
http://www.calculator.net/heat-index-ca ... &x=78&y=29

http://www.weatherfrog80.bplaced.net/te ... Mobile.php

Best Regards

Georg
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"Deus mare, Friso litora fecit" (God created the sea, Frisians the coast).

Best Regards

Georg

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Jachym
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Re: Heat Index calculation wrong?

Post by Jachym » Wed Sep 13, 2017 4:58 pm

I will fix it, the HI should only be calculated when T>26.7, otherwise it should show "--"

MeteoTwischkamp
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Re: Heat Index calculation wrong?

Post by MeteoTwischkamp » Wed Sep 13, 2017 6:57 pm

Thanks a lot Jachym.
"Deus mare, Friso litora fecit" (God created the sea, Frisians the coast).

Best Regards

Georg

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Reinhard
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Re: Heat Index calculation wrong?

Post by Reinhard » Thu Sep 14, 2017 1:05 pm

Now Windchill shows "--", too. Is this ok?
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Jachym
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Re: Heat Index calculation wrong?

Post by Jachym » Thu Sep 14, 2017 1:57 pm

Yes, windchill has upper limit too (if I remember correctly 10C, if the T is above 10, windchill is not defined and it also depends on wind speed, it is only defnied above certain value, I cant remember exactly)

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Reinhard
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Re: Heat Index calculation wrong?

Post by Reinhard » Thu Sep 14, 2017 4:24 pm

Thanks for respone. I will look at it this evening - it should get cold and windy outside. ;)

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