"I think it's going to be a question of how the Chinese markets react," said Chris Gaffney, president of world markets at EverBank.
"With the Fed meeting next week it's really going to be a volatile time period. We don't have a lot of data to move markets," he said.
In the meantime, traders are keeping an eye on commodities for indications of stabilization.
Copper jumped 5.28 percent Tuesday for its best day since May 2013, following August China trade data that showed demand for the metal . Overall, dollar-denominated exports from the country fell 5.5 percent in August from the same month last year, while imports declined 13.8 percent.
John Caruso, senior market strategist at RJO Futures, is looking for some follow-through in copper Wednesday. "You could certainly see some continuation especially since copper closed near highs," he said. "You could see a delayed reaction in gold."
The precious metal settled down 40 cents at $1,121 an ounce despite the weaker dollar.
Oil settled down 11 cents at $45.94 a barrel, posting a less-extreme move after a series of volatile swings in the last few trading sessions.
"That is a good sign for the global economy. As they put risk trades back on that's a good sign for equities," Gaffney said.
"If it stays stable I think you could see money moving into these markets," he said.
Many strategists still see economic conditions supportive of a September rate hike, but they noted markets were increasingly pricing in a delayed rate increase.
The U.S. dollar traded mildly lower against major world currencies as expectations of Fed tightening diminished.
The Australian dollar and New Zealand dollar held about 1 percent higher against the greenback in late trade Tuesday. The euro traded higher above $1.12 and the yen traded near 119.85 against the U.S. dollar. Emerging market currencies such as the Mexican peso and Russian ruble also gained nearly 1 percent against the dollar.
That "indicates to me firming global economic growth," said Mark Luschini, chief investment strategist at Janney Montgomery Scott.
Traders will eye Wednesday morning's Job Openings and Labor Turnover Survey for continued support of the improving labor market. The producer price index and consumer sentiment both due Friday are the few key data out before the Fed meeting.
"With inflation and consumer confidence somewhat influential to the Fed's thinking, everything else in between is just noise," Luschini said.
Before then, investors will digest Chinese inflation data. The producer price index and consumer price index are scheduled for release at 9:30 p.m. ET Tuesday (9:30 a.m. Wednesday, Beijing time), according to the National Bureau of Statistics of China.
Gaffney said markets now expect slower growth in China coupled with more stimulus. The easy monetary policy forecast also likely holds for the United States, according to markets.
It "looks like people are more confident the Fed is not going to increase rates and we get more global recovery," he said.
The FTSE, German DAX and French CAC 40 each closed up more than 1 percent Tuesday. U.S. major averages rebounded after the Labor Day long weekend to post gains of about 2.5 percent, their second-best day of the year.
The outperformed with gains of 2.7 percent to 4,811.93, out of correction and up 1.6 percent for 2015.
The S&P 500 closed up 2.5 percent at 1,969.41, also out of correction territory, or within 10 percent of its 52-week highs. The Dow Jones industrial average ended up 390 points to 16,492.68, within 0.2 percent of breaking out of correction mode.
Bruce Bittles, chief investment strategist at RW Baird, said the S&P 500 will likely remain in the 1,900 to 1,990 range "until the Fed does something next week."
"The volatility obviously is going to continue into late September," he said.
The CBOE Volatility Index (VIX), widely considered the best gauge of fear in the market, fell more than 10 percent Tuesday to below 25.
Despite the decline from 30 level, "the whole term structure of the VIX has been shifted higher. You're still seeing elevated volatility expectations into next year," said Daniel Deming, managing director at KKM Financial.
On the VIX, "typically it's pricing for increased volatility to the downside," Deming said. "The pattern to this point, the market has been unable to hold gains."
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He said if the S&P could hold above 1,988 that could signal an uptrend in the short term.
The stock closed Tuesday up 2.78 percent at $112.31 a share, up 1.75 percent year to date.
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