They dont stop feeding, but do tend to shy away from feeding on the bottom, as long as you are not a lazy carp angler the fishing "if anything" will improve on a hot sunny day, all you need to do is get up and work a little harder for your quarry, stalking and surface fishing are the most productive ways of fishing in such condition, a bait in the right place is worth a day in the wrong, keep low, keep quiet and search them out, their there for the taking