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.
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.