Don't worry about the temperature. Store in shade or a cooler. Just don't leave it in a closed car or sitting in the sun and you should be fine. Common sense applies. I grew up shooting all kinds of film in temps that were in the 90's from May through Sept and never had a problem with heat fogged film. I've had film in camera bags and coolers without ice for a week in the desert with daily highs of 100-106 F (>38 C) with no problems.
Have fun! If I were going, I'd pack a second body to shoot something like Fuji Pro 160S, a lower contrast fine grain film that captures color nuances well. But that's just me enjoying your trip vicariously.
Watch out for condensation on & in both your equipment and films.
The biggest problem is morning and evening - when the RH) is highest.
Take you camera in/out of any air conditioned hotel/restaurant in a bag - any bag (a zip-lock one is good for this)
The outer surface of the Bag will take all the condensation allowing the camera to warm up/cool down in its own non condensing air pocket
Give the camera about 30 mins to adjust to its new temperature before getting it out of the bag when going inside/outside
The film is OK in its sealed canisters – but again follow the 30 min rule.
As said above – don’t leave camera/lenses/film to cook in a closed sunny car if you can avoid it.
If you cannot – stuff them in the gap between the bottom of the front seats and the floor. It’s the coolest place in the car.
The high temps you get inside cars left in the sun can also kill batteries – take some spares & leave them in the hotel as back-up.
I live in the Caribbean, and I've never had any problems with respect to film freaking out over the climate here. So, have fun and don't worry about it. DO worry about your safety, however: the Caribbean is not crime-free.
Much sweat (pun intended) over nothing. Temp and RH nothing to be concerned about in any manner. Those are right about what we have here in FL on the coast in the summer.
BTW, RH is highest at the lowest temperature, usually right before the dawn.