That is usually the time of year we go, adn the best time, I think- the ocean temp is like bathwater, mmmm...and the weather is perfect, clear and not too much rain...but windy! but the breeze is nice, it keeps off the few bugs that might be around and keeps you from sweating too much.
Evening are also gorgeous, no need for even a light sweater normally, unless maybe you will be sitting oceanside.