Some sites are saying that today is National Ice Cream Soda. I celebrated it on the 20th, as did many other organizations. I'm not sure what's up with this duplicate holiday, but I can't find any other food celebration for today. (It's National Meteor Day, so I suppose you could celebrate with a Southern Bound Meteor if you're of legal drinking age.)
With this heat affecting most of the nation, I think everyone would be perfectly happy having another ice cream float.