Stock market futures pointed to more Wall Street woes, with equities under pressure from a Spanish bailout request ahead of this week's European summit.
The Dow fell about 1 percent last week, while the Standard & Poor's 500 dropped 0.6 percent. The Nasdaq tech barometer actually gained 0.7 percent, but the broader tenor of the market was negative due both to the problems in Europe and a weakened domestic economic picture.
Markets looked for more direction from Europe and awaited a possible ruling from the U.S. Supreme Court on the future of President Obama's nationalized health care plan.
With so much uncertainty on the horizon, markets are likely to be volatile through the summer.
"We still believe the global equity markets will trace out a very choppy advance during the second half of the year," said Sam Stovall, chief equity strategist at Standard & Poor's. "As a result, we think investors will continue to drive with their low beams on, being willing to make only short-term investment commitments."
Futures indicated an opening decline approaching 1 percent.
German chancellor Angela Merkel and French president Francois Hollande are expected to clash over his proposals to introduced common bonds across the euro zone, with Merkel expected to stand firm in her stance against them.