Any day when the temperature rises above 100 degrees F, it is alright to have ice cream for supper.
You didn't know this rule?
I have it on good authority from a white-haired woman I met at the grocery store, while aimlessly cruising the frozen food section. She was the "when I am old, I will wear purple" sort, who probably also eats dessert first, because life is uncertain. In other words, a good role model.
Well, today it only reached 98. So we settled for frozen yogurt.