(Reuters)—Texas oil refineries shut by cold-weather disruptions may take several weeks to resume normal operations, industry experts said on Friday, helping to push up fuel prices. About a fifth of oil processing was halted by power outages and shortages of natural gas and water this week. Average retail gasoline prices rose 6 cents on the week and are up 9 cents in the last month, to $2.33 a gallon, the American Automobile Association said. It forecast inventories would fall, keeping prices higher through month’s end. “We are 2 1/2 to three weeks away from restoring most operations” at affected refineries, said Andrew Lipow, president of Houston-based consultancy Lipow Oil Associates. The refinery shutdowns will depress prices for U.S. crude oil and widen the spread between U.S. and Brent crude, Paul Sankey of independent energy researcher Sankey Research said in a note. He forecast “heavy pressure on US crude prices from …