Power output of panels generally goes down as the temperature goes up. As Ghurd said, follow the manufacturers instructions on the installation and leave them well ventillated and they should be fine there. As for the batteries, self discharge generally becomes greater at higher temperatures, and the overall battery life becomes shorter, and watering for flooded batteries a little more often. I would site them in a cooler location if I could find one, but I would think that they should be fine otherwise. Rich