February Nymex natural gas (NGG24) on Thursday closed +0.153 (+5.73%). Nat-gas prices on Thursday extended this week’s rally to a 6-week high. A change in U.S. weather patterns to colder temperatures will boost heating demand for nat-gas and is fueling short-covering in nat-gas futures. Forecaster Atmospheric G2 said the northwestern part of the U.S. and Plains are seeing temperatures shift colder from Jan 9-13, and over the next two weeks and beyond, a weather pattern change will begin to unfold that will result in a “significant Arctic cold shot” in the U.S. Nat-gas rallied Thursday despite …