"RWood" wrote :

It's probably been answered before - what are the cloudiest UK sites
that have 30-year averages, or at least fairly long records? Someone
on another forum cited Kinlochewe from the Met. tables, but I
understand it has significant daylight loss.

Yes, the trouble is that the climatologically cloudiest parts of
the UK and Ireland are those very areas where most stations
have poor horizons (and, yes, Kinlochewe among them). Of low
level sites I guess Baltasound (on Unst in Shetland) averages
(CS) about 1020 hours per year; higher up, Great Dun Fell, some
850m up in the northern Pennines, had an average (again, CS)
of just under 1000 hours though how much used to be lost
through rime/ice accretion on the sunshine recorder is
anyone's guess. There's one site in the Irish Republic which
averages under 1000 hours (sorry, can't lay my hands on the
details) but I believe it, too, has a messy horizon.

Philip