Hi we have gone this time for two years the past couple of years. The crowds are typical summer crowds. For example Minion Mayhem can have easy 90 minute wait in stand-by but the express pass is only 20-30 minutes. However, I don't like crowds much but find it very doable for the parks. Volcano Bay will be a little more crowded at this time of year. I think you are better off during the week at the parks if you are only going one day. I love the summer so don't mind the heat either.