I'm not a tent camper..travel trailer here. That being said, I would think the heat in August would be ovewhelming. That's just my opinion. IF..I were to tent camp, I'd pick a less humid time of year. Also..having visited in August many times before, there are thunderstorms..often pretty severe, almost every afternoon. While we didn't actually mind, since they do tend to cool things down, I'm not sure I'd want to be in a tent during one of them. Or for that matter have to keep things dry. We've also visited in May(our favorite time of year..and if I were to tent camp..I'd go with that. We've also visited during the end of Sept. and end of Oct. both times the weather was much less humid than the heat of August.
I know there are a good many people who tent camp at FW..and enjoy it. I'm not sure I'd pick August for the first time to do it. Have you considered renting an RV or travel trailer? A bit more protection and relief from the heat should you need it. Or using the cabins in FW?