Market Insider

Start of Q3: A weaker period for stocks?

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June comes down to the wire on Wall Street

As traders watch developments on Greece, they are also teeing up next week for the start of the third quarter, often a weaker time for stocks.

So far, the S&P 500 is up 1.7 percent for the quarter-to-date, and it has historically averaged a 0.6 percent gain for the third quarter going back to World War II, according to S&P/Capital IQ chief equity strategist Sam Stovall.

But in the third year of a presidential term, it often does better, gaining 1 percent.

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The third quarter is also seasonally the time when stocks can be choppy. "History says when approaching the third quarter, fasten your safety belt. It's going to be a bumpy ride," Stovall said.

In the third quarter, six of the 10 key S&P sectors have averaged losses since 1989. Defensives—consumer staples, health care and utilities—have outperformed, as has energy, he said.