Don what are the geographical differences that are causing these different results? I would expect more rainfall in the West because they have an ocean to the west of them (the jet stream goes west to east for the most part) and less rainfall in the East because we have an entire continent to the west of us.
Another thing worth noting about the 60s is that although they were dryer, they had a lot more snow than the decades surrounding them-- my ideal combo, lots of snow in the winter and dry and hot weather in the summer. 1960-61, 1963-64 and 1966-67 were all classic and even historic winters.