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Cloudbase value?

Posted: Sun Dec 02, 2018 11:43 pm
by ConligWX
Hi there,

Apart from the FTP WDL Service, is Meteobridge going to support a Cloudbase value itself?

Re: Cloudbase value?

Posted: Sun Dec 02, 2018 11:45 pm
by admin
no and not planned.

Re: Cloudbase value?

Posted: Thu Dec 20, 2018 12:15 am
by ConligWX
Boris, I noticed in FTP WDL file clientraw.txt, Field 73 is Cloud Height which does have a value that has been somehow calculated. Could it not be added to Metebridge as a Sensor Template Value?

Re: Cloudbase value?

Posted: Fri Dec 21, 2018 1:02 am
by admin
It can be computed with template variables as follows (returns height in feet):

Code: Select all

#if#[th0temp-act.1:0.0]>[th0dew-act.1:0.0]#then#{*([th0temp-act.1:0.0]-[th0dew-act.1:0.0])*400*0}#else#0#fi#

Re: Cloudbase value?

Posted: Fri Dec 21, 2018 1:08 am
by ConligWX
Thanks!

Re: Cloudbase value?

Posted: Tue Jan 01, 2019 4:38 pm
by ConligWX
admin wrote: Fri Dec 21, 2018 1:02 am It can be computed with template variables as follows (returns height in feet):

Code: Select all

#if#[th0temp-act.1:0.0]>[th0dew-act.1:0.0]#then#{*([th0temp-act.1:0.0]-[th0dew-act.1:0.0])*400*0}#else#0#fi#
Boris, can you confirm this equation.

I found this on a wikipedia site: https://en.wikipedia.org/wiki/Cloud_base
  • Find the difference between the surface temperature and the dew point. This value is known as the "spread".
  • Divide the spread by 4.4 (if temperatures are in °F) or 2.5 (if temperatures are in °C), then multiply by 1000. This will give you cloud base in feet above ground level.
  • Add the results from step (2) to the field elevation to get cloud base above sea level.
*400*0 ?


(Temp. – Dew Point) ÷ 2.5 X 1,000 for °C values
(Temp. – Dew Point) ÷ 4.4 X 1,000 for °F values