Don't know if I really have one. I'll agree with those who posted pasta salad, mixed fruit bowls (melon, cantaloupe, watermelon, strawberries, pineapple, grapes), and smoothies (I'm rather partial to mango smoothies). Chilled berries are good, too. Strawberries, raspberries, and blueberries. Those are very enjoyable on a hot day.
Ice cream I'll eat anytime, even if the temps are single digits outside.