Definition of cloud layer

[EliasFransen]

Hello Gentlemen

I am currently studying for my CPL, and I came into a discussion with a couple of my classmates.

The definition of the cloud layer Overcast, is it 7-8/8 or just 8/8. As far as I remember from the Meteorology it is just 8/8, however as we checked this in the Swedish regulations for private flying, it states that it is 7-8/8.

We then called our METOFFICE, she was a little unsure, but then checked their definitions, which stated 8/8, but as I said, she was quite unsure.

We then called the Swedish Flight Planning Centre. The lady there was sure it was 7-8/8, but after checking in their papers, wich stated 8/8, she was also unsure.

We then called our local ATS unit, he was sure it was 8/8, according to some EU-policy or something.

We now have this problem, as the regulation states 7-8/8, shall we follow this, or wich one is correct?

Grateful for all replies
Elias

[Glamdring]

From what I was taught...

0 = Sky Clear
1-2 = Few
3-4 = Scattered
5-7 = Broken
8 = Overcast

[Spitoon]

The rules in the UK (which implement international Standards) areThe cloud amount can be expressed as:
a) FEW no more than quarter cover (1-2 oktas)
b) SCT over ¼ but no more than ½ cover (3-4 oktas)
c) BKN over half but not complete cover (5-7 oktas)
d) OVC complete cover (8 oktas)

[EliasFransen]

Thank you very much for your replies. I agree with you that it most probably is correct with 8/8. The thing that bothers me is that the regulation says 7-8, and I guess I'll have to follow that lead until I've confirmed that there is a typo in that document.. But anyhows, thanks again for your answers!

[OMGisThatJohn]

I'm not sure, but maybe the intended use is that between 7 and 8 is OVC.

"7 < Overcast <= 8" For clarification.

[AIRFLO]

Never understood why they dumped oktas...we can all cout up to 8...well, most of us can.

[mad_jock]

But how does breaking it down to oktas help pilots?

IFR

For planning purposes we need to know what the cloud base is which is anything over scattered.

And for live data we don't really care what it is as long as its above the minimum for the approach. And even then its only RVR that stops us making an approach.

VFR

Again cloud base is important But anything above Scattered and you can't really fly in it and still claim to be VFR. Anything above 1000ft agl is a bonus.
Again viz is the limiting factor.

Its a similar situation when they used to declare clouds above 10 000 ft how exactly that was meant to help us I don't know.