On Monday, August 27, natural gas futures dropped to a seven-week low, as the U.S. National Hurricane Center downgraded Tropical Storm Isaac to a Category 1 hurricane. Natural gas futures with October contract tumbled 1.1% to $2.707 a million British thermal units. In the meanwhile, meteorologists predict that Isaac will spur short-term shutdowns of 85 per cent of the U.S. offshore oil production capacity and 68 per cent of the natural gas output.