It will be very sticky (hot and humid)! Dont forget the love bugs that will be swarming around you (they dont bite, bug spray wont keep them away, and they are everywhere). Afternoon storms are routine, and dont forget, Sept is the peak of hurricane season.
Shorts, tees, comfy shoes that dry out quickly, waterproof bags for your camera/etc, rain ponchos....if you have kids a rain cover for the stroller, towel to wipe it off, and a swimsuit so they can play in the water fountains and Ariels Grotto. You may even want to do that! Drink lots of water and take it easy. A nice long lunch in a cool restaurant works for us!
alison