IMO, it really depends on where you're from and what kind of weather you're used to.
We went the first week of December last year... had people mention to me that it's gonna feel colder than it really is cause of the humidity, etc, etc.. but being from Ohio, I guess I'm used to (at times) extremely cold, high humidity weather... I did pack sweatshirts, and a light winter coat.. but for most of our time down there, we were all in jeans and a long-sleeved t-shirts.. couple days in shorts. Did wear my coat each evening, but in all honesty, probably didn't really need it. Think the coldest it got while we were there was low 30's one evening, and that's the only time I felt like I really needed my coat. Never needed gloves/hat, never felt like we needed them.