The same warm temperatures that you enjoy so much are your battery's worst enemy. Unlike cold weather where a battery may begin to show signs of weakness, in hot weather you may not have any warning that your battery is about to fail. You should know that your battery has a much tougher job during extreme conditions.
Hot weather combined with smaller, cramped engine compartments creates high under-hood temperatures.
This causes accelerated degradation and corrosion of battery components - resulting in reduced battery life. The older the car, the greater chance for problems. Combine an old battery and high temperatures, and you're asking for trouble. To be on the safe side, you should get your battery tested. Better yet, if your battery is more than 3 years old or you live in a hot climate, you may want to consider replacing it.