I closely watch market historical patterns. The first thing I'd like to say is that nothing works 100% of the time. But as a rule of thumb, I think following the month-end and holiday patterns works fairly well. I also observe weakness before options week as generally a good entry point. The seasonal Spring-Summer vs. Fall-Winter pattern is another interesting one. I think if we keep our eyes on the day-to-day, I think we can anticipate and increase our returns based on some of these patterns.
Along that line comes a column from Mark Hulbert on Sy Harding's MACD adaptation of the "Sell in May" seasonal market pattern. Worth a read, IMHO.
Not a recommenation, just an observation. And as Yogi Berra might say, "It's hard to do predictions, especially about the future."
And nothing that has worked in the past is guaranteed to work in the future. Also from Yogi, "The future ain't what it used to be."
If you notice, down in the article is a comparison between how Sy Harding versus Jeffery Hirsch. Each appears to follow the formula a bit differently, and have achieved different results.
(And that's a picture of Cheryl Burke from Dancing with the Stars. Has nothing to do with market seasonality, but I couldn't force my fingers to type in Sy Harding in the Google image search.)