With Tropical Storm Gustav expected to become a hurricane again and heading for the Gulf of Mexico, oil people were preparing for the worst and several companies were evacuating much of their personnel from off-shore facilities just in case.

Crude prices for December delivery closed at $115.75 a barrel, down 2.40.

The storm's projected course takes it through the heart of U.S. offshore energy production, threatening about 25 percent of domestic oil and 10 percent of gas output.

Oil's advancement suddenly halted Thursday after a bigger than expected climb in U.S. natural gas supplies renewed concerns about weaker energy demand.

Natural gas prices led the losses in the energy sector Thursday, with October natural gas down 55.8 cents, or 6.5 percent, to close at $8.05 per million British thermal units.

Heating oil was down 7.17 at 319 cents a gallon and refurbished gas was down 4.72 cents a gallon.

At the pump, U.S. motorists paid an average of $3.660 for a gallon pf regular unleaded gasoline, slightly lower than Wednesday's $3.667.