The hurricane season starts on June 1 and ends on Nov 30. What that means is that the conditions are most favorable during that time. Last year the hurricane that was heading for Siesta Key/Longboat Key but ended up devastating Tampa area came through on August 13.
That said, I would not worry about it too much. I live on Siesta Key year around and we deal with the possibility but have not been directly hit since I've moved here in '95. Came close couple of times but lucked out. The hurricane path is not that wide, so the chances of it hitting the spot that a tourist may be visiting for a week or two are very slim.
Can't tell you anything about the resort on our neighbor island.
And YES it will be hot and sticky in August. The water will be nice and warm, almost hottub temp.
Enjoy you stay and make sure you visit Siesta Key too!!!