Stocks brace for Bernanke

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NEW YORK (CNNMoney) -- All week, investors have been counting down to Federal Reserve Chairman Ben Bernanke's speech. With the big event just hours away, U.S. stocks were headed for a slightly lower open Friday.

Dow Jones industrial average (INDU), S&P 500 (SPX) and Nasdaq (COMP) futures were down between 0.1% and 0.3% ahead of the opening bell. Stock futures indicate the possible direction of the markets when they open at 9:30 a.m. ET.

Despite Thursday's slide, stocks are up about 3% this week. The market momentum has been attributed to investor hopes that Bernanke will announce new measures to spur economic growth when he gives his speech at Kansas City Fed's annual retreat at Jackson Hole, Wyo., at 10 a.m. ET.

"The Federal Reserve remains in the spotlight, with many observers wondering what -- if anything -- Fed officials can do to help promote economic growth," said Bob Doll, chief equity strategist at BlackRock.

At last year's meeting, Bernanke prepared the market for QE2 -- a bond-buying program that is widely credited for supporting stocks earlier this year.

Market wants Bernanke to be Mighty Mouse

Doll thinks a new asset-purchase program is an "unlikely prospect," but he said the Fed may have other steps in mind. He added that it will be important to gauge the Fed's intentions and outlook during Bernanke's address Friday.

"The uncertainty over the future of Fed action is clearly one of the risks faced by investors," Doll said. "The central bank likely wants to remain on hold until more information is available, but continued deterioration in financial markets would likely increase the odds that the Fed would ease in some way."

Meanwhile, as Hurricane Irene makes its way up the East Coast toward New York City, exchanges are prepared to resume trading as usual Monday.

"We have contingency plans in place for such events, with the goal of having the market up and running while ensuring the safety of our people," said a spokesman from NYSE Euronext, the parent of the New York Stock Exchange.

The NYSE was closed for a day in September 1985, when the eye Hurricane Gloria hit western Long Island, New York.

Economy: The Commerce Department said the U.S. economy grew at a revised annual rate of 1% during the second quarter, down from a previously-reported 1.3%.

The University of Michigan's consumer sentiment survey comes out at 9:55 a.m. ET. The index is expected to rise slightly to a reading of 55.4, from the multi-year low of 54.9 reported two weeks ago.

Companies: Tiffany's (TIF) stock jumped 8% in premarket trading, after the luxury jeweler posted higher-than-expected earnings and sales for the second quarter.

Shares of Pandora (P) climbed 7%, as second-quarter revenue spiked 117% to $67 million -- beating analysts' forecast for $61 million. But the online radio company's stock is off almost 17% from where it debuted in June.

Halliburton (HAL, Fortune 500) is on a hiring spree this year. The company is planning to create as many 15,000 jobs globally, including 11,000 in North America, according to a statement released late Thursday.

World markets: European stocks lower in morning trading. Britain's FTSE (FTSE) 100 fell 1%, the DAX (DAX) in Germany dropped 2.5% and France's CAC (CAC) 40 lost 1%.

Asian markets ended the session mixed. The Shanghai Composite (SHCOMP) edged 0.1% lower and the Hang Seng in Hong Kong (HSI) shed 0.9%, while Japan's Nikkei (N225) added 0.3%.

Currencies and commodities: The dollar fell against the euro, the Japanese yen and the British pound.

Oil for October delivery slipped $1.11, or 1.3%, to $84.19 a barrel.

Gold futures for December delivery rose $6.40 to $1,771.00 an ounce.

Bonds: The price on the benchmark 10-year U.S. Treasury rose slightly, pushing the the yield down to 2.20% from 2.22% late Thursday.