July and August are our hottest months and Bass adapt to it. Water temps in the mid 80s and above make the bass seek comfort and food in specific ways. I'll get into smallmouth and largemouth separately.
Smallmouth bass need a good amount of oxygen in the water. Slower water will be starved of it but fast water take as lot of work for them to stay in. Look for slower water near fast water. If you add cover (rock overhangs, tree shade, log jams, etc.), you will find more fish. Fish will be unwilling to chase or make long runs for food so presenting slower moving flies is crucial.
Choose flies you can slowly bounce of the bottom or slow drifting bugs on top. This time of year, we rarely use baitfish patterns as much as we love to see them disappear. Clawdads, Crittermites, Wooly Buggers, and Tequeely fly patterns are out go to for subsurface flies.
Top water action is phenomenal but it should be subtle and slow. Foam and cork bugs create a nice initial splash, then wiggle the legs every 5 to 10 seconds as the fly drifts in the current. This is a lot more like fishing a trout dry fly than like stripping a popper.
Largemouth Bass don't need a ton of oxygen and can find a break from the heat by going deep or into heavy cover. A sinking line in deeper holes is not a bad idea but I prefer to find them shallow in cover.
Top-water flies are great for lily pads or near grass. Suspending baitfish on the edges of grass can tease them out too. Your standard bas poppers, Dahlberg Divers, as well as larger foam bugs work great. For suspending baitfish, Game Changers, Murdich Minnows, Pony Boys are my go to. In any situation in super hot water, the key is to let the flies sit still for long period of times and to keep them in the strike zone. In other words, SLOW DOWN.
If you're fishing for tidal bass, look for the fish in the lee of the current. If the water is moving, the fish are looking to eat.