Hi, I am also in south Louisiana. Tomorrow my chicks will be two weeks old, and they will be moving to the coop. They are currently in my garage (door open during the day), and even with a fan, it is a fight to keep temps near outside temps.
I have spent the last few days reinforcing my coop against predators (primarily snakes and rats), and adding ventilation. I found a small weather resistant vent fan (approx 5 inches square) that I put in one end to pull hot air out, made a mesh wire on frame door to the run to use instead of the solid door for ventilation, and when the chicks make the move, will put the fan they have now, near the outside of the new run door to give them a breeze in that part of the coop to cool down from the excessive humidity. Just a few ideas for maybe how to help them that I have run across the past few days.