It's always on a Monday night around homecoming. They build a pretty tall structure out of shipping pallets. It's fun to watch from a boat if you have access.
Also, there is a fireworks show that is almost as good at the 4th of July show on the first Saturday in December that is part of the Tropical Christmas Festival. They shoot them off from the same spot at the 4th of July show and there are usually only a few boats in the water so you dont have to deal with all the craziness that exists in July. We try to not miss this.