Toyota Repair: 97 Corolla Cooling Problem, radiator cooling fans, hot lanta

Question
In the last couple of days my corolla has started registering as HOT HOT HOT on the dash guage whenever I sit at idle or in slow traffic for any length of time.  If I flip the heat on (not fun here in Hot-lanta) it brings the temp guage down to a normal level and when driving at regular speeds it has no problems.  This only happens during the hottest part of the day, mornings are fine.  I'm not sure if it is related but in the last few weeks my A/C doesn't blow much cold air when driving at low speeds or at idle.  At regular speeds it blows icy cold.  Thanks for your help!

Answer
There are two things that it could be, the radiator cooling fans are not coming on or the radiator has a circulation problem, it may be partially clogged, the cooling fans are easy to check, the main fan should come on when the engine gets to operating temp, the A/C fan should come on along with the main fan when the A/C is turned on, the reason the A/C doesn't work is that when the engine overheats the high presssure switch shuts the compressor off, if you take care of the overheating problem the other problem should take care of itself.