By Sara Sjolin, MarketWatch

SolarCity slides premarket after earnings

LONDON (MarketWatch) -- U.S. stocks were poised for a weak open on Wall Street on Thursday, with futures hit by a sharp fall in oil prices and investors staying on the sidelines ahead of a raft of earnings reports and economic data.

Futures for the Dow Jones Industrial Average (DJH5) slipped 20 points, or 0.1%, to 17,973, while those for the S&P 500 index (SPH5) dropped 3.60 points, or 0.2%, to 2,091.80. Futures for the Nasdaq 100 index (NDH5) were flat at 4,386.00.

Markets had closed slightly lower on Wednesday, as investors wrestled with interpreting minutes from the Federal Reserve's latest meeting, which suggested the first rate hike might come later than expected. The report showed the central bank is worried about the low rate of inflation and slow pickup in wages, emphasizing the importance of those data points.

Data: Investors on Thursday might get more hints to whether wages are likely to improve, with a reading on weekly jobless claims due at 8:30 a.m. Eastern Time. Economists polled by MarketWatch expect 290,000 Americans filed for unemployment benefits last week, down from 304,000 the week before.

The Philadelphia Fed's manufacturing index for February is out at 10 a.m. Eastern. Economists expect a slight rebound to 8 from the sharp decline to 6.3 in January, compared with 24.3 in December. The leading indicators readings is scheduled for 10 a.m. Eastern as well.

Oil blues: Energy companies and oil-related funds were hit hard in premarket trade, as crude-oil prices slid below $50 a barrel. The oil slump came after data showed a whopping jump in U.S. oil stockpiles, which underscored concerns of a supply glut. Among oil-tracking indexes, the iPath Goldman Sachs Crude Oil Total Return Index ETN (OIL) fell 3%, and the Velocity Shares 3X Long Crude ETN (UWTI) slumped 7.7%.

ConocoPhillips dropped 1.7% ahead of the open, while Exxon Mobil Corp. (XOM) shaved off 1.2%, and Halliburton Co. (HAL) lost 2%.

Progress in Greece: The Greek government formally requested a six-month extension to its loan agreement, sending stocks higher in Athens. Senior eurozone finance ministers will meet later on Thursday to discuss the request, but it's not a given that they'll grant Greece the extension. The country's anti-austerity government has distinguished between a mere loan agreement and a continuation of the full bailout program, which it argues hurts the Greek society and economy. Germany said yesterday they were against approving just the loan extension without the conditions attached to the full rescue program.

The full Eurogroup of eurozone finance ministers is scheduled to meet on Friday.

Earnings: It's a busy premarket line-up on the earnings front: Wal-Mart Stores Inc.(WMT) is projected to report fourth-quarter earnings of $1.54 a share, according to a consensus survey by FactSet.

Reporting early, T-Mobile US Inc.(TMUS) posted fourth-quarter earnings of 12 cents a share, against a loss of 12 cents a share a year ago.

Priceline Group Inc.(PCLN) is forecast to post fourth-quarter earnings of $10.10 a share.

DirecTV(DTV) is projected to post fourth-quarter earnings of $1.39 a share.

Hormel Foods Corp.(HRL) is forecast to post fiscal first-quarter earnings of 64 cents a share.

Movers and shakers:SolarCity Corp.(SCTY) slumped 6.7% after the solar-energy firm late Wednesday said it swung to a fourth-quarter loss of 4 cents a share, from a profit of 28 cents a share a year ago.

Counterpart SunEdison Inc.(SUNE) was also in focus. The solar-energy company late Wednesday reported a smaller-than-expected fourth-quarter loss.

BJ's Restaurants Inc.(BJRI) could also be active after reporting a sharp rise in profit for the fourth quarter.

Other markets: European markets struggled for direction as investors digested developments in Greece's debt negotiations.

In Asia, Japanese stocks rose to a 15-year intraday high, while the rest of Asia closed mixed. Chinese markets were closed for the Lunar New Year celebrations.

Gold rallied, while the dollar (DXY) was slightly lower, after the Federal Open Market Committee minutes dashed hopes of a midyear rate hike.

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