Investors will be closely watching iPhone maker Apple's quarterly results after the closing bell. Shares of the tech giant have tumbled nearly 30 percent from their all-time high of $705 a share last September. Analysts expect Apple to earn $13.47 a share on revenue of $54.73 billion. (Read More: Apple Earnings Need to Overcome Technical Malaise)
"Expectations are already built—if Apple comes in as expected, I think we'll see the market bounce," said Adam Hewison, president of INO. "But the trend is technically and fundamentally down for Apple—there's still room for the stock to go lower."
Netflix, Amgen and Sandisk are among other notable companies that will post earnings this afternoon.
Meanwhile, the bill to extend the debt limit to May 19 received enough votes to pass the House of Representatives. The House passed the measure by a 285-144 vote, a bipartisan showing on an initiative brought by majority Republicans.
On the economic front, mortgage applications gained for the third-straight week, thanks to an increased demand for refinancings, according to the Mortgage Bankers Association.
In Europe, tech and healthcare stocks were among the gainers after SAP issued guidance for 2013 operating profit that beat market expectations and Swiss drug maker Novartis said it expects sales growth to pick up in 2014.
Meanwhile, Germany's Siemens, an industrial bellwether, posted a decline in quarterly profit, citing charges for a delayed high-speed train order.