I agree on bringing at least one sweatshirt. It can feel really good in the early morning and at night, especially if there is a stiff breeze. I was in Disney the last week in April last year and a light jacket would not have been enough for me. In fact, one day I had on a tee shirt, sweatshirt over that, and then a light jacket over both of those...and I was still chilly because the wind blew all day. Better to be safe than risk being cold!