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Wind Chill question...

Discussion and questions about Cumulus weather station software version 1. This section is the main place to get help with Cumulus 1 software developed by Steve Loft that ceased development in November 2014.
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Repairman77
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Wind Chill question...

Post by Repairman77 »

Running Cumulus 1 on a WH1080.

I am always puzzled by the strange graph of the Wind Chill on the temperature graph.

The zig-zags going from low to the same as temperature reading.

See graphs below; it doesn't seem to correlate with wind speed and temperature readings; I'm probably missing something here but if anyone can explain it in simple terms I'd be grateful.

Thanks,

Mike.
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Retired Radio and Electronics Engineer residing in Cambridgeshire, UK.
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daj
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Re: Wind Chill question...

Post by daj »

is it that Windchill is only measured when windspeed is above 3mph? Your windchill disappears as your windspeed drops to 3 or less

http://wiki.sandaysoft.com/index.php?title=Wind_chill
David
kippfordweather.uk
Cumulus MX & Raspberry Pi
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Repairman77
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Re: Wind Chill question...

Post by Repairman77 »

daj wrote:is it that Windchill is only measured when windspeed is above 3mph? Your windchill disappears as your windspeed drops to 3 or less

http://wiki.sandaysoft.com/index.php?title=Wind_chill
I think you've got it David; that fits in with the graphs. :D

Many thanks,

Mike.
Retired Radio and Electronics Engineer residing in Cambridgeshire, UK.
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Repairman77
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Re: Wind Chill question...

Post by Repairman77 »

Just a thought; would it be possible to alter the value in the .ini file (as mentioned in the link) so that it would display wind chill values below 3mph, even though they would be very close to the actual temperature?

Mike.
Retired Radio and Electronics Engineer residing in Cambridgeshire, UK.
TNETWeather

Re: Wind Chill question...

Post by TNETWeather »

By definition there is no wind chill value below 3mph though or when the temp is over 40°F (if I recall the temp correctly)
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steve
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Re: Wind Chill question...

Post by steve »

Repairman77 wrote:Just a thought; would it be possible to alter the value in the .ini file (as mentioned in the link) so that it would display wind chill values below 3mph, even though they would be very close to the actual temperature?
I think that because of the way the formula works, they come out exactly the same, or even slightly higher than ambient temperature. It's not designed to give figures below 3 mph.
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steve
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Re: Wind Chill question...

Post by steve »

TNETWeather wrote:or when the temp is over 40°F (if I recall the temp correctly)
50F: http://www.weather.gov/os/windchill/index.shtml
Steve
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Re: Wind Chill question...

Post by Repairman77 »

Thanks for the explanation chaps, I was thinking it would just smooth out the graph a little but obviously it wouldn't work with the current calculations.

Mike.
Retired Radio and Electronics Engineer residing in Cambridgeshire, UK.
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