The weather you describe is just typical Florida weather. Luanne's chicken runs are tucked under several shade trees, but it is still hot and humid come August in the shade. Just make sure they have plenty of shade. I live about two hours' to the east of Luanne, so same weather.But I'm watching the chicks I ordered from Eight Acres carefully (currently almost 10 weeks): I got 7 German New Hampshires (which I want to cross into the NNs), and since there was a 20 chick minimum, filled out the rest of the order with Blue Copper Marans and Olive Eggers. I've been watching the carefully - it can be hard to tell if they are going to have an issue or not. When they sit still and hang out, they pant and hold out their wings some, but not in distress type panting (like today, when it was only 86F and they were in deep shade) - when they decide to get up, they run around like there's no problem.
THAT BEING SAID... The Marans seem to have their mouths open more than the others, and occasionally a couple of the bigger Marans boys have looked a bit iffy (had me on the verge of getting a bucket, but then got up and toodled around). So I have a question for all you super hot weather chicken folks - any experience with Marans in heat? Since they are nice examples from a good breeder, and supposed to be good dark egg layers, I considered keeping a Maran cockerel with the Maran pullets. But I'm beginning to wonder if he will have a hard time making it through the summer...
Apparently, we are having a tropical storm come through the area today - the trees will certainly be happy with all the rain. It's been a little drier than normal (for Florida) so we have needed to water the young fruit trees added last month. I still have not hatched out any more really nice chicks like Bigfoot and his four sisters (from Oct 2015) and that is starting to irk me. The genetics are there, just need the right combination.
I've been rather busy with not only garden and fruit trees, but dairy goats and cheese making and this past weekend was a surprise acquisition of new rabbits. One is a pretty blue Rex furred doe, and for months I've been telling her previous owner, "If you ever want to sell her, I definitely want to buy her." Now she is mine!

I'm sorry to hear about Ron/hellbender's health issues. I too hope he recovers and makes it back to posting here; he certainly has a unique perspective on things.