* Costco June sales top expectations
* Initial claims, import-export prices due
* Bernanke comments cool stimulus-slowing ideas
* Futures up: Dow 149 pts, S&P 18.7 pts, Nasdaq 31.25 pts
NEW YORK, July 11 (Reuters) - U.S. stock index futures climbed on Thursday, after comments by U.S. Federal Reserve Chairman Ben Bernanke indicated the central bank was unlikely to scale back its stimulus measures earlier than expected.
Bernanke, at an economic conference in Cambridge, Massachusetts on Wednesday, said a highly accommodative monetary policy was needed for the foreseeable future, and that the U.S. unemployment rate of 7.6 percent overstated the health of the job market.
On May 22, the S&P 500 fell as much as 5.8 percent following comments from Bernanke which raised the prospect of an earlier-than-expected move by the central bank to scale back its bond buying program.
"(Fed policymakers) don't have any more clarity about what it going to happen in the future than any other human being on earth, but they do have clarity as to their actions," said Kim Forrest, senior equity research analyst, Fort Pitt Capital Group in Pittsburgh.
"Even though there is all this talk of transparency, it doesn't seem like it is paying off, the markets are as confused as ever."
The Fed chairman's comments sent the dollar lower and boosted commodities such as gold and copper. U.S.-listed shares of Barrick Gold climbed 4.4 percent to $14.62 while Freeport McMoRan Copper & Gold gained 2.4 percent to $28.25 in premarket trade.
The benchmark S&P 500 has risen 2.4 percent over the past five sessions, its longest winning streak since early March, on optimism over improving economic data and anticipation of a better-than-expected earnings season.
Investors await weekly initial jobless claims data and June import-export prices, to be released at 8:30 a.m. EDT (1230 GMT). Economists surveyed by Reuters forecast a total of 340,000 new filings. Import prices are expected to remain unchanged while export prices are expected to show a 0.1 percent decline.
S&P 500 futures rose 18.7 points and were well above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures gained 149 points, and Nasdaq 100 futures jumped 31.25 points.
Retail stocks will garner attention as they post monthly sales results. Costco Wholesale Corp reported June same-store sales that beat analysts' estimates, helped by higher fuel prices.
Analysts expect S&P 500 companies' second-quarter earnings to have grown 2.6 percent from a year ago, with revenue up 1.5 percent, according to Thomson Reuters data.
Advanced Micro Devices Inc jumped 7.5 percent to $4.28 before the opening bell, after Bank of America Merrill Lynch upgraded it to "buy" from "underperform."
European shares hit five-week highs, led by growth-sensitive stocks, while Asian shares hit a near four-week high after Bernanke's comments.