Natural gas futures extended gains Monday after weekend revisions to weather outlooks projected a bigger and stronger polar vortex over much of the U.S. in the coming days, bolstering expectations for a burst of gas-fired heating demand. Natural gas futures for December delivery were up 1.1 cents, or 0.3%, to $4.4230 a million British thermal units on the New York Mercantile Exchange, continuing a rally that has added more than 23% to prices since late October. Gas futures have risen in the nine previous trading sessions. Forecasters are predicting a larger and colder spate of weather in the coming days over the plains and Midwest states, that will reach as far south as Texas and push eastward as well through mid-November. Though the worst is expected to subside going into late November, temperatures are expected to remain much-below normal over the northeast, Midwest, Plains and parts […]