Use a guage to check your tire pressure.
Low tire pressure can cause a tire to overheat and fail. This is an obvious danger in excessive heat waves. Low tire pressure is dangerous as the weight of your vehicle will push down and compress the tire, generating high amounts of internal heat. Combine this with continual contact of the road will resulting in the tire literally breaking apart from the inside out. Making sure your tires are properly inflated insures they can stand up to the task of keeping your vehicle on the road.