We went the first week of October last year and will go again this year too. I think it's a great time to go b/c the crowds are manageable and we were able to do both F&WF whenever we wanted and there were 2 MNSSHP's we could attend. Or maybe 3 during our time-frame?
Our weather was amazing and I can't recall having any rain, but I was on pins and needles the weeks prior to our trip. Those damn hurricanes just wouldn't let up!