Hello, Nicole,
Having just returned from a very hot week at Walt Disney World, I can totally empathize with you! In fact, we, too, had reservations at Sanaa for mid-afternoon, but ended up arriving an hour earlier because we were just too beat from the heat after the morning at Disney's Animal Kingdom. Thankfully, Sanaa was able to accommodate our early arrival. It is one of my favorite restaurants, and I would hate to have missed dining there. Not only does it have deliciously unique food, but the ground floor views of the animals on the savannah are spectacular. We watched two zebras playing and chasing each other, and it was hilarious.
If I were in your situation, I would actually hold onto the reservation at Sanaa for now. As your trip gets closer, start to watch the weather to let you make a more educated decision. It could be a day filled with rain, so the park won't be as crowded or hot making it easy to spend the entire day there (there is so much to do!). Also, if it is raining, you wouldn't want to visit Blizzard Beach. You'll also find you have a better idea of what your energy-level is like once you begin your trip. Just keep in mind the
Disney Dining Cancellation Policy so you aren't charged if you do decide to cancel the reservation.
If you have any further questions, please let us know. Wishing you a magical trip! -
Kara