December Nymex natural gas (NGZ24) on Tuesday closed lower by -0.014 (-0.48%) Dec nat-gas prices Tuesday fell back from a 6-week nearest-futures high and closed slightly lower. This fall, above-normal temperatures in the US have curtailed heating demand for nat-gas and allowed gas inventories to build, bearish factors for nat-gas prices. Nat-gas Tuesday initially moved higher after the Commodity Weather Group said forecasts had shifted colder for the central part of the US from November 22-26, which should boost heating demand for nat-gas. Nat-has prices also had carryover support Tuesday from…