Key oil-producing countries won't meet until the weekend, but commodity traders placed early bets on the outcome.

Confidence a production freeze agreement can be reached during an Organization of Petroleum Exporting Countries this weekend in Doha, Qatar, sent crude and equities sky high on Tuesday: The S&P 500 added 0.97%, the Dow Jones Industrial Average climbed 0.94%, and the Nasdaq rose 0.8%. 

Rumors swirled earlier in the session that Saudi Arabia and non-OPEC member Russia have already agreed on the terms of a deal, though the Russian energy minister declined to comment on reports. West Texas Intermediate crude oil added 4.5% to $42.17 a barrel on Tuesday, its highest settlement of the year.

The energy sector was the main beneficiary of a crude rally on Tuesday. Major oilers Exxon Mobil (XOM - Get Report) , PetroChina (PTR - Get Report) , Total (TOT - Get Report) and BP (BP - Get Report) climbed, while the Energy Select Sector SPDR ETF (XLE - Get Report) added 3%.

Commodity analysts remain skeptical any deal among OPEC members will result in meaningful change, however, given many oil producers are already at record output, while Iran continues to add to a supply glut after sanctions against the country were lifted. 

"Traders may still be responsive to a happy photo-op from Doha, even though we think a freeze only cements a status quo, with rising Iranian production still pushing the OPEC total toward 33 million barrels per day, sustaining and extending the current market surplus," said Timothy Evans, ‎energy futures analyst at Citi.

The International Monetary Fund reduced its forecast for global growth to 3.2% in 2016, down 0.2 percentage points from its January forecast. The global organization had previously cut its 2016 outlook in October and July last year.

"Global growth continues, but at an increasingly disappointing pace that leaves the world economy more exposed to negative risks," IMF Chief Economist Maurice Obstfeld said at a press conference on Tuesday. "Growth has been too slow for too long."

Alcoa (AA - Get Report) , which unofficially kicks off earnings season, reported weak first-quarter results after the bell Monday. Its stock fell 2.7% after missing revenue estimates in its first quarter on an aluminum slowdown. The industry bellwether reported a 15% slide in revenue to $4.9 billion, its third straight quarter of declining sales. Analysts estimated sales of $5.2 billion. Adjusted earnings of 7 cents a share were down from 28 cents a year earlier.

The company also said it could cut up to 2,000 jobs, adding to the 600 jobs already eliminated this year and another 400 cuts planned. CEO Klaus Kleinfeld said that the layoffs would be mostly in Alcoa's aerospace-parts business and would be spread across many countries.

Forecasts for the rest of the earnings season look disappointing. Analysts anticipate earnings for companies in the S&P 500 will fall 7.9%, their fourth straight quarter of declines and the steepest drop since the second quarter of 2009.

"What managements have to say about the months ahead will be carefully watched," said David Joy, chief market strategist at Ameriprise Financial. "It is easier to overlook the immediate past if the immediate future looks brighter. And earnings growth is expected to turn positive in the year's second half. The full-year forecast now estimates overall growth of 2%, as only energy, materials and telecom end the year in the red."

Lower energy prices and a stronger U.S. dollar continued to impact import prices in March. Import prices climbed just 0.2% on a month-over-month basis, far below estimates for 1% growth. February prices were revised to show a 0.3% contraction. Export prices remained flat, as expected, after a 0.4% contraction a month earlier.

The U.S. economy will likely grow just below 2% this year, meaning it will be suitable for a rate hike this year, Dallas Federal Reserve President Rob Kaplan told CNBC on Tuesday. In a speech a day earlier, Kaplan said April was likely too soon for a hike, but a June increase could be a possibility. Kaplan is not a voting member of the policymaking committee this year.

Juniper Networks (JNPR - Get Report) slumped 7.4% after cutting its forecast for its first quarter. The networking company expects first-quarter earnings between 35 cents and 37 cents a share, below analysts' estimates of 45 cents a share. Juniper said the weaker outlook was due to softer business demand and unfavorable timing of deployment from some telecom companies.

ArcelorMittal (MT - Get Report) added 3.2% after its shares were added to Goldman Sachs' Conviction Buy list with a price target of 5.4 euros. The company announced plans to repurchase bonds in euros and dollars on Monday after raising cash from a recent $3 billion rights issue.

Starbucks (SBUX - Get Report) declined after Deutsche Bank downgraded the stock to hold from buy. The firm said the downgrade was a valuation call based on a $64 price target. Starbucks shares fell 2.3%.

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