A comment in a bourbon-related thread caused me to think about this topic.
I tend to regard the few scotches I drink as year-rounders, with possibly a slight bias toward warm weather, not cold as the original poster suggested. Perhaps that's due to the nature of the scotches I prefer.
The only single-malt I've bought more than once is Highland Park 12. I can't say it's worth the money, compared to bourbon of the same price, but it's a fine drink IMO. I gave away a nearly full bottle of Laphroig 10 (I think it was). I tried Lagavulin 16 in a bar once and struggled to finish it. However, it was interesting enough I'd like to try it again someday. Of the blends, I like Famous Grouse and Johnnie Walker black -- don't care for the red, haven't tried others. I can drink Dewar's, my frugal son's favorite, but I'd rather not. I gave away a barely touched bottle of Chivas Regal 12.
Bottlings that I at least finished but don't expect to replace include Macallan 12, Dalmore 12 (finished it last month -- on my shelf three years), Glenlivet 12 and Glenfiddich 12. If any of those ages are wrong, just subsitute the youngest available.
My point is that I'm guessing that a tendency to regard scotch as a winter drink might reflect a fondness (and willingness to pay for) much older, more heavily peated scotches, possibly of the barrel-proof variety.