NEW YORK (TheStreet) --Are you still recovering from last week's stock-market volatility?  It's not over yet, according to one market expert.

Stock-market investors should prepare for some bumpy sessions in the next few weeks, according to Brian Jacobsen, chief portfolio strategist at Wells Fargo Advantage Funds.

Jacobsen looked at 25 past previous bull-market corrections and found that they usually lead to even more volatility in the days that follow.

"Typically, the next 20 days out, you have heightened volatility of around twice what you had going into the correction," Jacobsen said, "So I think that investors and traders can brace themselves for some of these bigger moves."

The bout of renewed volatility will come just as the Federal Reserve prepares for a crucial two-day interest-rate policy meeting. Jacobsen expects the Fed will announce a rate hike in mid-September, and said that the stock market is beginning to price that in.

"The nice thing about the market move that we saw last week and the week before is that from a valuation perspective, the stock market is in a much better place to absorb a rate hike," he said. "So maybe what we've already seen is people coming to grips with the fact that if it's not September, it's probably going to be October for a rate hike."

Over the weekend, Federal Reserve Vice Chairman Stanley Fischer said there's a "good reason" to believe that inflation will rise back toward the Fed's 2% target.

Jacobsen said economic data that will be released between now and the September meeting could reaffirm that the Fed should make a move.

He said small and mid-cap stocks look attractive, as do cyclical and business-to-business technology stocks. Jacobsen added that his favorite place now are emerging markets, with the exception of politically volatile countries such as Brazil and Turkey.