This is just me but I think the heat bothers the fisherman more than it bothers the carp. I have caught carp in backwaters that were hotter than bath water. And, I have caught them on Roberts in the middle of the afternoon on the flats in July and August. Sometimes it's so hot that, when I wade back to the boat to go home, I have to splash lake water on the carpet so I can crawl back into the boat without scaulding myself. Carp are pretty tough fish and I don't think the heat bothers them as much as you might think.