The bull run could soon hit turbulence once the record-breaking earnings season ends, according to Nuveen's Brian Nick.

"We'll see in November and December as good news headlines go away – what, if anything – takes over and what kinds of bumps we get between now and the end of the year," the firm's chief investment strategist said recently on CNBC's "Futures Now."

But Nick, whose firm has over $900 billion in assets under management, notes it wouldn't permanently harm the rally.

"If you're looking forward into the end of next year, the light is still green for the U.S. economy and for corporate profits," he added.

"Between now and then, we see the markets anywhere between 8 percent and 10 percent higher, and that's basically in-line with our expectations for earnings growth," the investor said.

A strong earnings season has been one of the main drivers for the fresh market highs. With more than half of S&P 500 Index companies reporting so far, nearly three-fourths of them have exceeded Wall Street estimates, while 17 percent missed and 9 percent came in-line.

Since JPMorgan Chase kicked off earnings season on October 12, the and Dow have closed at intraday highs six times, while the Nasdaq reached the same milestone five times. On Friday, both the Nasdaq and S&P closed at new records.

However, Nick points out that the next couple of months could become bumpy as the markets deal with uncertainty over factors such as tax reform, which is currently advancing through Congress.

"I go back and forth with how much of this tax reform package is priced in. Part of the problem is that we don't have a bill, and we won't have one until next week," said Nick. "There's about a 50 percent chance that we do end up with nothing. I think there's only about a one in three chance that looks similar to what we have now."

He said the markets will also need more clarity surrounding the next two Federal Reserve meetings, and the potential new leadership there. President Donald Trump is expected to name a replacement to current Fed Chair Janet Yellen, but has not made a firm decision on who will ascent to the world's most powerful central bank.

Despite the possible near-term headwinds, he's reiterating his bull case for next year.

"I think we are going to see stronger earnings not only in the U.S. but abroad, and that's going to be good for global equities across the board," Nick said.