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CumulusMX cloudbase

Posted: Sun 27 Sep 2020 9:34 am
by brookr
Hi
A question from a relative Newbie to CumulusMX. 19 August 2020 launch. http://leedsweathercentre.co.uk/index.php
It's almost at the stage of where I want it to be - but still one or two gremlins to sort out. PaulMy has kindly assisted and got me to where we are today. many many thanks to Paul.
Still issues with Options either not working or working with a little manual help. Uploading files etc.

One question I have on the cloud base image is "where does CumulusMX source the temperature alongside the cloud image? It seems too low for the temperature at the respective heights.
Any help welcome.
Thank you
Rob :oops: :shock:

Re: CumulusMX cloudbase

Posted: Sun 27 Sep 2020 11:41 am
by mcrossley
Cumulus provides neither a cloud image, nor a temperature at altitude value. They must be a product of the template you are using.

Re: CumulusMX cloudbase

Posted: Sun 27 Sep 2020 12:50 pm
by beteljuice
As Mark says ...

The file that's doing everything is http://leedsweathercentre.co.uk/cloudbaseCUmx.php

The cloudbase height is (in your case) from METAR EGNM, the script adjusts the temp to cloudbase.
Have you set your station 'altitude' for the script - that could make a difference

Re: CumulusMX cloudbase

Posted: Sun 27 Sep 2020 7:05 pm
by ConligWX

Re: CumulusMX cloudbase

Posted: Sun 04 Oct 2020 5:03 pm
by brookr
Thanks Simon
Correct , my cloud base has been set to Leeds Bradford Airport - EGNM, which is around 760 feet above sea level, whereas my station altitude is 333 feet.
I wasn't aware that the METAR supplied a temperature at cloud height :?:

Re: CumulusMX cloudbase

Posted: Sun 04 Oct 2020 5:21 pm
by freddie
brookr wrote: Sun 04 Oct 2020 5:03 pm I wasn't aware that the METAR supplied a temperature at cloud height :?:
METARs don't supply cloud height temperatures. It's probably computed from the ground level temperature using the dry adiabatic lapse rate (approx. 3 degrees Celsius reduction per 1000 feet).