Air conditioning

Why is it that when it gets hot our air-conditioning fails us. We were driving my Honda CRV to go to Alisha's pool yesterday,( because it was in the high 80's, and it was a Sunday afternoon and we wanted to get cool) when we heard this funny noise and all of the sudden my air stopped shooting out cool air. NOOOoooooooooo! I was just thinking the other week how nice it was that my car was working so well and that I haven't had any problems. Needless to say, since we live in the south and it is suppose to be getting up to the 90's next week, I guess I will have to get it fixed. It never gives me a problem in the winter, no, it waits until summer!