Go casually smart in a navy and white blazer and a long sleeve shirt. One actually can look cool and fresh under the oppressive heat. The proof is right here
Navy and White Blazer with Long Sleeve Shirt Dressy Summer Outfits For Men
For a smart look, rock a navy and white blazer with a long sleeve shirt — these two items fit really well together. So if it's a boiling hot summertime afternoon and you want to look dapper without putting in too much work, this outfit will do the job in next to no time.