Prestwick Flying Club would do its best (who I fly with) but they don't have any full time instructors. However they are (I suggest) the most experienced, including an ex RAF test pilot and a current BA captain. Worth having a chat to see what's possible. If you can get instructor availability you wont be disappointed! Don't be put off if you can't get someone on the phone - it is a club rather than a profit making school but voice messages are checked (and a phone back will depend on BA shift patterns). There is good availability with our "new" Robin which I enjoy flying.
A perhaps better bet would be Prestwick Flight Centre who have (I believe) one full time and a number of part time instructors.
Prestwick pretty much never fogs in and there is a cross runway, meaning you can fly in more wind conditions. As its runway is pretty much at sea level (and the runways are huge), cloud base is less of an issue.
If you are unlucky there will be a series of low pressure systems that come through just as you start which keeps you on the ground (no fun to fly in rain). However if you sign up for lessons and are flexible to go whenever the weather is good, you should still be able to get well through the course, and grounded instructors will be happy to have chats on theory you have difficulty with (at Prestwick Flying Club, almost certainly without charge).
ACS are now doing training from Glasgow but that means you take off from Glasgow, then fly to Cumbernauld or Prestwick to do circuits, which to me would waste a bit of time and probably cost more. Cumbernauld is a great place but I know there have been times that I haven't been able to fly in due to cloud (as it is higher up) when Prestwick has been fine.
If you're Glasgow based, you really don't want to be travelling to Perth or Fife on a regular basis to fly. You'd spend much more time on the road than in an aircraft.
My theory - if you don't get signed up with a club / school, you'll certainly stay on the ground!