Market Insider

Start of Q3: A weaker period for stocks?

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.