The selloff in U.S. stock futures during premarket trading on Tuesday is another sign that volatility is here to stay, said Julian Emanuel, U.S. equity and derivatives strategist at UBS.
Dow futures were down about 230 points on Tuesday, while S&P futures traded about 30 points lower. Both indexes signaled a decline of about 1.5 percent.
"We think that the calm that we saw for most of this year and actually since 2012 has shifted, but it doesn't mean that the bull market's ended by any stretch," Emanuel told CNBC's "Squawk Box."
Emanuel marked China's surprise devaluation of its currency last month as the start of the extreme volatility, noting that it played into the Federal Reserve's decision to leave rates near zero last week. He said he now expects the Fed to raise rates between December and March.
Read MoreWall Street set for a tumble
Now, Washington is contributing to uncertainty as it moves toward an Oct. 1 deadline to fund the federal government, Emanuel said. Negotiations have been stalled by Republican lawmakers who have promised not to approve any spending bill that funds Planned Parenthood.
Lawmakers may also become embroiled in another debt ceiling debate December, Emanuel noted.
However, he advised investors to minimize the obsession with day-to-day swings.
"It's going to be a more volatile environment, but the underlying facts are that the economy remains strong," he said. "When the 10-year is yielding around 2.2 percent, we think investors are going to get paid to wait to see an earnings recovery."