Earnings Thursday morning are expected from Goldman Sachs, Citigroup, Blackstone, Charles Schwab, First Republic Bank, KeyCorp, and M&T Bank. UnitedHealth, eBay, Sherwin-Williams, PPG and Phillip Morris also report.
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After the close, earnings are expected from Google, Schlumberger, Mattel, Advanced Micro, Celanese and Cintas.
But first, traders will focus on the ECB, which is not expected to take any action but will be closely watched as it focuses on Greece. The euro fell to $1.09 Wednesday, as markets awaited the Greek parliament vote on austerity measures.
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The U.S. dollar also gained against the Canadian dollar and other commodity currencies after Canada's central bank announced a rate cut.
Alan Ruskin, Deutsche Bank's head of G-10 foreign exchange strategy, said the markets look forward to a dovish Draghi.
"I think he can remain a little more optimistic on the economy. The latest lending surveys point to improvement. He can point to idea that QE seems to be working. He'll remain committed to the idea that QE will be maintained through September of next year," Ruskin said. "From a policy standpoint, he's going to sound nice and dovish."
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Yellen, who spoke Wednesday morning before the House Financial Services Committee, will testify before the Senate Banking Committee at 2:30 p.m. On Wednesday, she reiterated that the Fed could raise rates this year. She did give a nod to concerns about China weakness and the Greek debt crisis, but she didn't see them as problematic enough to derail a rate hike.
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The central banker reinforced that the Fed is watching the economic data, and noted that auto sales have improved, reflecting that households have the wherewithal and confidence to buy big-ticket items. But she didn't harp on the decline in June retail sales that some in the markets thought might make her sound more dovish.
"She's not using the excuses that are available to back away from a tightening. She's still suggesting there will be at least one tightening this year," Ruskin said.
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Yellen did stress that the rate hike trajectory will be slow, as the Fed has been telling markets. Treasury yields moved lower as the yield curve flattened, meaning yields at the low end move lower less quickly than long-end rates.
Besides central banks and earnings, there are jobless claims at 8:30 a.m.; the Philadelphia Fed survey at 10 a.m.; and the NAHB homebuilders' survey, also at 10 a.m.
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