January Nymex natural gas (NGF26) on Friday closed up sharply by +0.226 (+4.46%). Jan nat-gas prices soared on Friday to a nearly 3-year nearest-futures high as forecasts of frigid US temperatures are expected to boost nat-gas heating demand.  Nat-gas prices have rallied sharply over the past week as late-autumn temperatures have remained well below normal and are expected to persist, boosting heating demand and shrinking nat-gas storage levels.  Forecaster Atmospheric G2 said Friday that significantly co ...