I have done 3 USA tours I would say take clothes you can layer up or off. So for me its a vest / T shirt with an over blouse and then maybe a cardy or a fleece and a light jacket. I was in New England when I went in September 2006 and the weather was fine we did have some very warm day's. I don't know if you have been with JY before, but if not the clothes really are just smart casual, don't bother to take posh clothes for the evening, The 3 USA tours I have been on have been pretty full on, so I would go for comfort You will have a great time

Cindy