In reply to chaotic_chris:
Despite days getting shorter and a wee bit cooler, Scotland's fickle weather can be surprisingly good during September. The show stopping Autumnal gales are usually a few weeks away. Whilst climbing on dry, warm, sun kissed rock being a wee bit rarer, I'd be optimistic for getting at least a couple of dry days for getting some quality scrambling / mountaineering type routes under your belt during a week around Glen Coe and Ben Nevis at that time of the year. Alternatively it could pish doon and blaw a hoolie aw week....roll the dice and hope for light easterly winds.