This is the 'dullest market in decades,' but get ready for some turbulence ahead

The dog days of summer have brought on the "dullest market in decades," according to note from Tom Leveroni, CFA & Shourui Tian, Ph.D of Nautilus Investment Research.

The duo says the the S&P 500 has spent the last 10 trading sessions in a 92 basis point range, the tightest in 22 years. The lackluster action has come in the wake of the UK voting to leave the European Union, the Fed gearing up for its next rate hike, and uncertainty surrounding the upcoming US election.

The lack of volatility in the market is evident by the recent performance of the VIX, or Volatility Index, which recently fell below 12.00 for the first time since 2014. While not at its lowest level in decades, it remains well below its long-run average of 19.79. Additionally, the monthly closing low of 10.42 set in January 2007 isn't too far off.

Andy Kiersz/Business Insider/Data from Bloombeg

So what should we expect from here? According to Leveroni and Tian, a two-week trading range of less than 150 basis points "have been followed by significant market gains 6 months later (27 up, 3 down, avg +7.23%)."

This seems to jive with Nautilus' call on July 11 that the S&P 500's all-time high was "the mother of all buy signals."

However, traders should be warned that turbulence lies ahead.

The pair cautions that August through October period is typically the most volatile for the markets, and that "turbulence begets more turbulence."

They suggest you "enjoy the calm while it lasts."

Nautilus Investment Research