than I am pretty sure you have up to, and including labor day. Of course, I think more people follow this up north where I am from, than down south, where I now live. Maybe just the times though. Although people down south sometimes start wearing white after Easter vs. Memorial day. But, it gets plenty hot down here around then, so kind of makes sense to pull out your "lighter wear".
Either way, I really wouldn't worry about it. Enjoy the party.