As you can see interestingly, November is always "down" and December is always "up"; September is mixed, while October has been up for the last 3 years, but for this year I would say it might be a mixed month due to the strong rally in September with rather steep slope of rising.
How well history repeats itself depends on the actual outcome 3 months later.
Happy Investing!
2010 Sept - Dec
2011 Sept - Dec
2012 Sept - Dec
2013 Sept - Dec