Weather - for me, I try to layer. Mornings can be nice and cool, so I'll wear capris or a sundress, but always have a cardigan. The kids usually have a hoodie sweatshirt. Of course it often comes off during warm sunny afternoons, but indoors can be chilly.
Plan for a little of everything: chilly or warm. Never hot all day like summer. Most spring break trips, it's been warm enough for the kids to swim. Sometimes me too, but I'm thin skinned, so prefer it at least 80 degree F to swim!