Scotch mist 
noun [mass noun]
A thick drizzly mist of a kind common in the Scottish Highlands.It's lovely to see everyone in the city again and I'm pleased to see that Glasgow has the same sort of Scotch mist as we do back in Glenbogle....
- We had to provide equipment to demist it, otherwise you'd only have seen them through Scotch mist, Masters said.
- The entire ballet is set amid a swirl of supernatural Scotch mist.