Why an oil inventory fall won’t boost prices much: Goldman

Declines in U.S. oil inventories and capex may boost prices modestly in the near term, but production growth will remain too strong for substantial gains, Goldman Sachs said.

"While the decline in the U.S. rig count has been faster than we expected, it remains insufficient in our view to balance the U.S. market in 2016," Goldman said in a note dated Monday. "Prices need to stay low for longer to achieve a sufficient and sustainable slowdown in U.S. production growth."

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The aggressive capex and activity cuts may offer some modest upside to its $40 a barrel forecast over the next three months, but the risk to its longer-term $65 a barrel forecast is to the downside, Goldman said.

Wild ride

Oil prices have taken a wild ride recently, surging more than 6 percent in U.S. trade Monday, with WTI futures for May delivery at $52.14 a barrel after reports from private company Genscape showed inventories in Cushing, Oklahoma, a physical storage hub, had fallen. But that spike followed an around 4 percent drop Thursday on expectations a pending deal with Iran could boost supplies significantly. Speculation that Cushing facilities would soon be full, sending more crude back onto the market has weighed on prices recently. Government data on supplies is released Wednesday morning.

While U.S. crude storage capacity is being tested, Goldman expects the inventories will peak in April, before declining from May to September, with last week's data from the U.S. Energy Information Administration showing a decline in weekly production offering a potential early sign the market is stabilizing.

But that could prove temporary.

"Any meaningful price recovery on evidence of declining production and U.S. crude inventories would further undermine the U.S. rebalancing process," it said.

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In addition, production could continue to grow in April, with producers focusing on "high-grading," or shifting resources to their highest-quality wells, as well as productivity gains and shorter drilling times, Goldman said. It expects U.S. production will grow by 700,000 barrels a day this year.

Downtrend not over

Others also expect the recent gains in oil prices aren't a sign the long downtrend has ended.

"It's a bit of a head fake," Matt Smith, a commodity analyst at Schneider Electric, told CNBC Tuesday. He attributed the rise to a combination of pent-up demand over the long holiday weekend and a weaker dollar as well as the Genscape data.

Pipeline and crude storage tanks in Cushing Oklahoma.
Justin Solomon | CNBC
Pipeline and crude storage tanks in Cushing Oklahoma.

Additionally, oil had dropped sharply last week on concerns a framework deal on Iran's nuclear program could lead to a flood of oil flowing out the country as sanctions were lifted. But analysts believe it will take months, if not a full year, for Iran's oil exports to begin and even longer for investment in the country's crumbling oil infrastructure to boost its production to previous levels.

"The immediate bearish reaction to this news has then been sort of considered and somewhat unwound again," Smith said. But he added, "The reality is that there is a rebalancing going on here and we're likely to see more weakness before we head truly stronger from here."

—By CNBC's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1. CNBC's Patti Domm contributed to this article.