I don't know anything about Lagganlia, so I don't know whether that fits.
If it's an inhabited place, even a tiny one (see Altnaharra) then I'll take
it.

It's inhabited. Seehttp://www.lagganlia.com/


I see from looking at the site (for an outdoor activity centre) that
they appear to have a Davis AWS there reporting current conditions
(although the name of the site is not given, I'm assuming it's
actually there). Might be worth watching on some late summer nights
with clear, calm conditions as I recall Laggalia often had
surprisingly low minima even sometimes with only short clear spells at
this time of year.

They also had -24°C there in Jan 1982 and the thermograph trace
reproduced in Weather (Dec 1984, p 362, where the site was
consistently refrerred to as 'Lagganalia') showed that the air temp
remained below -10°C from sunset on 7 Jan to almost noon on 11 Jan
1982. I don't know that the site of the Davis is the same as the
climat station, but I'm guessing as it's such a small place they can't
be far apart ...