The S&P 500 just posted its 68th straight trading day without a drop of 1 percent or more.
That's its longest streak since 2006, when it saw a streak of 94 sessions (from July 14 to Nov. 24). The index on Thursday closed 0.36 percent in the red, and opened Friday morning slightly higher ahead of President-elect Trump's inauguration.
Since Oct. 11 (when the market dropped 1.24 percent), the S&P 500 has risen 5 percent. In 2006, the S&P 500 rose just over 13 percent in those 94 trading days from July 14 to Nov. 24.
To BK Asset Management's Boris Schlossberg, the relative market quiet won't last very long.
"I think the road ahead could be bumpy, because volatility is one of the few things in the financial markets that you can count on," he said Thursday on CNBC's "Trading Nation."
Schlossberg, noting the market's recent streak of low volatility appearing to be its lowest since 2006 — "And you can remember what happened in 2007 and 2008" — said he believes it's "almost inevitable" that the market will see some kind of turbulence ahead.
"There's definitely some sort of a storm coming. I don't know if it's going to be mild, or more severe, but it's almost impossible for me to believe that we're just going to have this very, very calm, pretty natural calm for much longer. Something's going to trip the markets and they're going to get corrected," Schlossberg said.
Options traders appear to be pricing in an increased volatility ahead, said Matt Maley, technical analyst and equity strategist at Miller Tabak.
"You got a lot of people betting a lot of money that just in the next month, you're going to see volatility," he said, adding that when the S&P 500 trades in a tight range for an extended period, and then breaks out, it typically sees a sharp move.
Recent underperformance in the small-cap Russell 2000 index, Maley wrote in an email to CNBC, could raise a red flag for the S&P 500's performance. If the Russell 2000 breaks meaningfully below its recent "sideways" range, it could indicate a break to the downside in the S&P.
"Right now, the Russell is testing the bottom-end of ITS range, so if it breaks down further, it will raise a lot of concerns for the S&P. This is especially true since the Russell was a leading indicator for the S&P (to the downside) in the summer of 2015," Maley wrote.
LPL Financial in a recent post noted that volatility rarely stays very low for long.
"Of course, it doesn't mean volatility can't be beneath the long-term average for another year or two, but be aware this period of a lull in volatility is getting long in the tooth," senior market strategist Ryan Detrick wrote.
"Coupled with economic uncertainty, despite some upside to growth prospects with the new administration, this further increases the chances of much more volatility later this year."