Thanks for the info! I've seen some pictures of people wearing sweatshirts/coats/scarves in November and December, and some of t-shirts and shorts, so I think we'll have to pack a variety and play it by ear.
And not to be a creepy weirdo, but my eyes bugged out a bit when I noticed that not only are you from a neighboring town (I'm from Fishers), but you seem to be going to Universal the same time I am! (I'll be in Disney on 11/30 and 12/1, and Universal on Dec 2-4.)