1993 Honda Accord

Hi, I noticed that when I travel long distances with my a.C on and finally stops for a while, the temperature gauge starts tending towards the red mark. If I resume acceleration on the road again, it starts dropping gently. On a particular day, it got all got all the way to the red zone and overheated- I check the bonnet n discovered the fans had stopped, then I put off the ac and then started the car again and the fans picked. My assumption is that the car the car tends to overheat after a long drive with ac on and then a stop (while the ac is still running). While on the highway the temp is perfect. Do u think it has to do with my radiator pores(dunno wat they call it), maybe enough air aint passing thru them. Pls advice. Nb: I ve changed my relay n the fan hasn't stopped since after the first time it happened.