January Nymex natural gas (NGF26) on Wednesday closed up by +0.155 (+3.20%). Jan nat-gas prices rallied sharply on Wednesday and posted a nearly 3-year nearest-futures high.   Weather forecasts of colder-than-normal weather in the US, which will boost nat-gas heating demand, have sparked fund buying of nat-gas futures on Wednesday.   Forecaster Atmospheric G2 said below-normal temperatures in the Northeast and Great Lakes will last through the end of this week and return after the middle of the month.  Na ...