Wall Street pundits maintain the stock market is overdue for a correction, just in time for September, historically the worst month of the year for equities. But financial turbulence next month is likely to be followed by sunny skies later in the fall, fund manager Jim Jubak writes in his column for MSN Money.

The average September performance of the Standard & Poor's 500 from 1971 through 2012 is a loss of 0.52 percent, the worst for all twelve months of the year.

But calendar caution is not the only reason for investors to be wary this September, Jubak noted.

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He cited the potential pullback in the Federal Reserve's monthly bond-buying program, which might begin next month and could take a security prop away from the stock market.

Also emanating from Washington, D.C. is a renewed battle between Republicans and Democrats over the big federal budget deficit, accompanied by a new struggle over the debt ceiling.

Jubak noted the S&P 500 fell 7.2 percent last year in the run-up to the fiscal cliff budget crisis. "This time around, we've got two crises on the same timetable — the budget and the debt ceiling — and it's hard to imagine that the market wouldn't have a similar negative reaction."

Following a September correction, Jubak said there is room for another bullish period for stocks. "While we're due for a correction, we're not way, way overdue," he explained. "The average time between corrections in bull markets since 1932 is 29.8 months, according to InvesTech Research. That's one every 2½ years, and we're currently two years away from the September 2011 correction."

In addition, he noted, stocks are not overvalued, leaving them room to go higher. "Even with the current very long rally to all-time highs, U.S. stocks aren't spectacularly overvalued. ... The degree of overvaluation isn't at the extreme level we usually see before a drop greater than 10 percent."

Also, he said there are few investment options other than U.S. stocks. "It's harder to take money out of U.S. stocks when European and emerging market equities don't offer an attractive alternative.

"I'd deal with the coming September madness by selling losers and taking profits in my portfolio now so that I had cash available for bargains in October and November," he professed, adding that he expects a 7 percent retreat in stocks in September.

Many Wall Street traders are girding for a serious market downturn in the near term, CNBC reported.

Jack Bouroudjian, CEO of financial services holding company Bull and Bear Partners, told CNBC he has never been more bearish on the U.S. stock market.

"The time has come to say that the 'easy' money in equities might be behind us unless we see real growth in the GDP [gross domestic product] numbers and forecasts increase for top-line revenue from corporate America over the next couple years," he said.

Bouroudjian told CNBC a catalyst for a market correction could be the appointment of a new Fed chairman after Ben Bernanke's term expires in January. He noted that the last two times when the Fed chairmanship changed — in 1987 and again in 2006 — the stock market sold off sharply.

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