We go the week of Labor Day every year, so it's quite hot. It's relative to what you're used to, as well. We're in S Louisiana, so 1,000 degrees and 500% humidity is normal for us
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We're park commandos, and my kids are old enough to to need naps any more, so were in the parks from rope drop till lights out. We dress lightly, cotton shirts, comfy sandals or flip flops (DH and I switch back and forth with athletic shoes during the week), hair up in pony tails, tank tops etc. Also, we take a Camelbak to help stay hydrated. We bring the big one, with water for the four of us. We keep bottled water in our resort fridge, fill up the Camelbak before heading out, and refill it around 2:00ish in the park. You can get ice anywhere
. That way, I'm making SURE we all have access to enough water. Yes, the Camelbak is heavy at first, but I really love having the cold backpack on, haha! As we drink, obviously, it gets lighter.
We always try to have lunch inside, if possible. Usually Cosmic Rays in MK, ABC Commissary in DHS, Sunshine Seasons in Epcot. We love Flame Tree so much that we don't care that its not air conditioned, but its still quite cool and shaded.
And of course, there's an air conditioned gift shop or dark ride just around the corner from wherever you are. We try to do attractions and rides with no A/C either early or late (safari, etc).
For little ones in strollers, I'd recommend a stroller fan and a collapsible umbrella. My son is very fair skinned so even when he was in a big convertible stroller, I attached a clamp-on umbrella to keep him covered all the time. I later clamped it onto his umbrella stroller when we switched to that. Keeping him shielded from the sun helped a lot, and he could turn on his stroller fan as well. You can get those little battery operated fans on a lanyard for your kids before you go (cheaper than the Mickey ones lol). My daughter, the oldest, loves filling her mister fan (we caved and got her a Mickey fan a few years ago) with ice cold water to mist herself with.
Again, we're used to crazy heat/humidity, so it's no big deal, but if you're not used to it or have little ones, a little preparation and flexibility in the parks should make your trip wonderful
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