It can be hit or miss, so pack for any weather and wear layers. Mornings/evenings tend to be cool, but we've been down there where it's down right cold and we needed winter jackets. We've been there when it rained (although it hasn't been bad/heavy rain, more a shower passing through) and we've been there when it's 75.
We've gone Thanksgiving week for the last 7 years (sans 1) and I now pack jeans, tshirts, sweatshirts, jackets, gloves and scarves. And some shorts for those in my family who prefer those.