We all know that when the weather gets warmer here in the south that many fish begin their way down to cooler temperatures. This is true with most fish like big, largemouth bass and of course, catfish. Those big fish will come up early in the mornings and the evenings, but in the middle of the day when it is as the warmest, they are more likely found toward the deep water.
Catfish can be caught during the day. Most people make the mistake of fishing for them in shallow water. In Santee, SC you can find people fishing on the weekends in very shallow water. They will catch an occasional catfish, but if they want the larger ones they need to go deeper. My brother and I would go to the exact same place as they were fishing, but we knew the area and where there was a huge drop off. We would get stares as we pulled in 15 pounders.
They would acutally come over to us and ask us what we were using for bait. I would tell them anything between huge nightcrawlers and/or stink bait or fish pieces. They would reply that they were using the same thing, and I would ask them how far out they were casting. They would answer by saying not far, because in the evenings they have caught nice fish in the shallow water, but in the middle of the day they need to fish deeper. They tried it and they started catching fish. At least that info kept them from getting closer and closer to me and my brother's fishing spot!