When we go anytime after October, we fly in our jeans, heavy socks, turtlenecks, sweatshirts and windbreakers. We pack light mittens in our bags. That way, if and when we need the heavier clothing we have it but it doesn't take up a lot of room in our bags. We found that it is nice and warm in the sun during the day. But if you are standing in the shade for a long time it can get chilly. And the nights can be chilly. We try to bring along the heavier stuff and leave it in a locker, just in case.