Local Orlando channels may be airing news segments. In Florida, the sun has been taking a break most days allowing more rain and thunderstorms to fill the sky - even if the temperatures are still high and humid. This may lessen the chances of an opening ceremony.
We may also want to consider that the Media and VIP week Universal Studios held in mid June may have been the official opening ceremony. Cast members including Matthew Lewis, Tom Felton, Bonnie Wright, Evanna Lynch, Robbie Coltrane, Helena Bonham Carter and the Phelps brothers were in attendance to broadcast webcasts on Universal Studios' page as well as attend a red carpet event. Soft openings in early July have allowed park guests to see the Diagon Alley park and ride the Hogwarts Express before its official opening date.
Tomorrow on July 8th, park guests may just be allowed to cross over the barricade-free area and into the magical land of Diagon Alley - without a grand ceremony for the expansion.