We've gone a few times in June and will be again this year. Late June (6/24-7/4/07). We went very close to that time last year and the year before that mid July. The last week in June wasn't too bad heat or crowd wise, but around the 4th the crowds really pick up. Just plan ahead to stay cool. And plan your days ahead of time. Don't bother with too much make up..it won't stay on. Go for comfort over fashion on park days. A mid day dip in the pool does cool you off, but we just stay in the parks for the whole day...to us it's a pain to go back to the hotel, swim and get cooled off and then go back out and get all sweaty again. We scatter the park days with rest days. It does rain every day. My favorite time to go is early Feb. you can pretty much walk on the rides with no wait.