Just when you thought those gas prices were falling, rising crude oil costs are likely to drive them higher again, according to the Detroit Free Press. Drivers pulling into metro Detroit filling stations this week could pay an additional 2 to 6 cents for each gallon of gasoline amid supply concerns in the coming months. And the situation might get worse, the Free Press reported. Though the summer driving season is over, analysts say high demand for heating oil this winter could cramp gasoline inventories over the next few months. Additionally, the Organization of Petroleum Exporting Countries (OPEC) will cut its crude oil production starting in early November, and that is also increasing oil prices, the Free Press said. Since OPEC announced in late September that it was cutting production, oil prices have risen about 20 percent, said AAA Michigan spokesman Jim Rink. "OPEC has a price band where they want to keep oil," Rink said. "OPEC is considering further cuts in December." Rink said gas prices could rise further in the coming weeks if supplies remain tight, according to the Free Press.