A rush of earnings news could help steer the market's direction on Tuesday, after Citigroup's earnings beat provided kindling for a market rally Monday.
Tuesday's earnings reports include Johnson and Johnson, Coca-Cola, Charles Schwab and Northern Trust before the opening bell, and Intel, Yahoo and CSX after the close.
Corporate commentary on the outlook and on the current business climate and economy is being watched most closely, since earnings are not expected to be stellar. S&P/Capital IQ expects a 1.2 percent decline in S&P 500 companies' profits.
"What's going to be important to us is ultimately management saying, 'we're not seeing the same slide,'" said Mark Luschini, chief investment strategist at Janney Montgomery. "I think that's what you've got to listen for. Otherwise, I don't know what breaks this market out of its trading range of (S&P 500) 1830/1840 or the highs of 1880/1890."
Luschini said he expected the S&P 500 to head toward 1800 when it broke 1840 last week: "There's some weak support there, and you start to get support in the 1760 range. I'm not bought in to today's rally."
Economic data could also be a factor, after the best retail sales gain in 18 months Monday helped fire up the rally that started with Citigroup. Both earnings and economic data are being scrutinized to see how much first-quarter sluggishness can be attributed to weather impact.
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Stocks finished Monday sharply higher, with the up 146 points at 16,173, the up 14 points at 1830, and the Nasdaq up 22 points at 4022. Traders watched developments surrounding Ukraine, and stocks moved higher even though anxiety about the tense situation with Russia sent buyers into gold and oil.
On Tuesday, there is CPI consumer inflation data and the Empire State survey, both at 8:30 a.m. The National Association of Home Builders survey and Treasury data on international capital flows are released at 10 a.m.
"I'm not expecting much in the way of CPI to alter the view that there is none (inflation), and no need for the [Federal Reserve] to do anything heroic," said Luschini. He's watching the Empire State survey for a snapshot of the manufacturing economy.
But Peter Boockvar, chief market analyst at Lindsey Group, said even a blip higher in the consumer price index could give markets a jolt.
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"I think it is a big deal. We've had multiple data points pointing to a bottoming in inflation," said Boockvar. He noted the surprise 0.5 percent jump in the producer price index (PPI) last week. The March number was the largest since June, 2013, due to an increase in food and trade services prices. PPI was down 0.1 percent in February.
He added that a jump in compensation reported by the National Federation of Independent Businesses in its monthly survey could also be a telltale sign. According to the survey, 25 percent of employers reported raising compensation and two percent reported cutting it, the highest number boosting compensation since 2008.
The Reuters/Jefferies CRB index, which tracks 19 commodities, is at its highest level since October, 2012, Boockvar said.
"Gasoline prices are at the highest level since July," he said. Beef prices are also rising, and are at levels not seen for nearly three decades.
If inflation does show up, it would surprise markets since the consensus view is that there are no signs of inflation, he added.
"If there's one thing that could handcuff Fed policy, it's a rise in inflation. According to the Fed's measure, we're far away from it. I think it's important in gauging the timing of the exit strategy. A faster uptick in inflation could hasten that exit strategy faster than the Fed thinks," he said.
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The Fed has targeted an inflation rate of 2 percent for hiking rates. "You get back to that 2 percent level faster than the Fed thinks and you're going to see rate hikes faster than the Fed expected," he said.
The Fed has worked to assure markets that it would keep rates low for a long time, even as it winds down its bond purchasing program. It removed language from its statement at its March meeting about an unemployment threshold of 6.5 percent for rate hikes. Fed officials said the target was no longer relevant and that it was not intended as a trigger for hiking rates.
What else to watch
The Fed should make a few headlines Tuesday, with a handful of Fed speakers making the rounds.
Fed Chair Janet Yellen makes opening remarks at 8:45 a.m. for the Federal Reserve Bank of Atlanta Annual Financial Markets Conference. More importantly and probably more newsworthy, Yellen speaks at midday Wednesday at the Economics Club of New York, where she will also answer questions from economists.
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Atlanta Fed President Dennis Lockhart makes welcoming remarks at the Atlanta Fed conference at 8:30 a.m., and Philadelphia Fed President Charles Plosser moderates a panel there at 3 p.m.
Boston Fed President Eric Rosengren speaks at 4 p.m. on the economy in Bangor, Maine, and Minneapolis Fed President Narayana Kocherlakota speaks on the economy at 8 p.m. at a town hall in Fargo, N.D.
—By CNBC's Patti Domm. Follow her on Twitter @pattidomm.