NEW YORK (CNN/Money) - Worries about Hurricane Rita's threat to the Texas Gulf Coast sent oil and other energy prices higher Thursday, dampening the outlook for stocks.

U.S. stock futures were down in early trading, indicating a lower opening for stocks, as Rita reached the most destructive Category 5 status and oil companies shut down offshore oil and gas platforms as well as refineries.

The storm, now measured as the third strongest on record, is expected to hit the coast sometime early Saturday morning. If it is as bad as now expected, consumers are likely to see gas prices soar far above the record prices that followed Hurricane Katrina.

Michael Schlacter, chief meteorologist for private weather service Weather 2000, said that it now appears the eye of Rita could come ashore near Port Arthur, Texas, near the Texas-Louisiana border. That area has its own concentration of refineries, but Schlacter warned that Rita is now so large that refineries further down the coast in the Texas City-Houston area are also at risk.

Offshore oil rigs and platforms, even some of them further east off the Louisiana Gulf Coast, are also at risk from the heavy surf being kicked up by the storm as it moves through the Gulf of Mexico.

"She is spending the longest possible time she could spend in the Gulf, and because of that she has days and days to build up momentum and churn up the waters," he said.

The threat of Rita sent oil prices sharply higher in early trading again Thursday.

The November light crude futures contract for NYMEX gained $1.23 to $68.03 a barrel in electronic trading, while the November contract for Brent crude rose 99 cents to $65.72. Natural gas futures also soared, reaching a record high, with platforms off the Texas Gulf Coast seen to be at risk.

Major markets in Asia closed lower Thursday on oil price concerns. Consumer electronics and entertainment conglomerate Sony (Research) lost 1.7 percent in Tokyo trading before it announced plans after the market close there to cut 10,000 jobs globally and close a number of factories as it aims to cut costs by $1.8 billion.

Major European markets were also lower in early trading.

Treasury prices were higher, cutting the yield on the 10-year note to 4.16 percent from the 4.17 percent level late Wednesday. The dollar gained ground against on the euro and the yen.

In corporate news, Citigroup (Research) announced late Wednesday that it faces a Securities and Exchange Commission probe against two of its asset management units for disclosure issues. Shares of the Dow component lost 33 cents, or nearly 1 percent, to $44.82 in after-hours trading.

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