was sitting in the drive through yesterday when i noticed the temp guage rising, to just below the red. it was raining and like 15 degrees outside! once i started rolling again, the temp dropped quite quickly. then as i pulled up at the lights the old girl almost died. quickly into neutral and a squirt of juice kept her going but im unsure what the deal is. water pump maybe??? also engine light came on. unsure of what code yet.
If it did it at idle I'd also look into the serviceability of your clutch / mechanical fan. I believe an easy way of checking it is to spin it by hand- if it free spins it's a problem. If it has resitance and only spins a quarter turn it's good to do. Obviously check it with the engine off ;)