Just some musings, sort of related to the question posed -
It occurs to me that this is the time of year when summer suits are being blown out of inventory by many retailers. Sort of like buying a parka in March.
Both good and bad to that. The good is that, of course, buying a suit that's been seasonally price reduced gets you "more suit for your money." The downside, is that inventory from which to choose may be a little limited.
Frankly, the whole notion of "summer suit," or suit seasonality in general, is a lot less meaningful today, than it was generations ago. It's not completely gone, of course. It's still decidedly weird to wear heavy tweed on a 90 degree day in August, or to sport seersucker when it's snowing outside. But I'd venture to suggest that the vast majority of suits sold today are essentially of a year 'round variety. Various reasons for this, with perhaps the most significant being the prevalence of climate control in office buildings, restaurants, theaters, cars, etc.
With the exception of a khaki poplin suit and a seersucker suit (both inexpensive items, worn only infrequently, and only for social occasions), I don't think any of my suits could honestly be categorized as "summer suits." And believe me, Baltimore definitely experiences its share - and more - of hot, humid summer weather.
I likely own more "summer shoes," than I do summer suits.
Pictured below, my Allen Edmonds "Hampstead," brown woven wingtip oxfords. Definitely summer shoes. I think AE discontinued this style a while back.