This would be a translation of average clouds.
In meteorology we distinguish 3 layers:
From the ground till about 6000 feet. We. call these clouds: (groundlayer fog): LOW CLOUDS
From about 6000 feet towards about 15.000 feet: MIDDLE LAYER CLOUDS translated in Dutch:
‘Middelbare bewolking’ , NOT Gemiddelde bewolking.
From about. 15.000 till over 30.0000 feet: HIGH CLOUDS.
PAUL

I love your Windy- programm.
However as a retired Dutch meteorologist I have to switch to a site where I can import my data to find out what the ‘Steadman’ windchill-factor is.
Well is it possible that you calculate it.
Would be great.
Regards,
Paul Citroen
e-mail: pengcitroen@gmail.com