When I climbed Ben Nevis in July 2007 there were large patches (half a football pitch size) of snow that had not melted and were significant enough, I would have thought, that they would not melt before the first winter snows arrived. This is a slight aside from the first snowfall issue, but links in with Essan's point about a sub-arctic climate. I am sure there will have been snow areas that survived this summer......
Anyway good to see the Scottish thread up and running, here's to a good season in the highlands 🙂
Near Leatherhead 100masl (currently living in China since September 2019)
Loving the weather whatever it brings, snow, rain, wind, sun, heat, all great!