The polar vortex will soon be history, but its impact could linger for months in one vital industry. The U.S. natural gas market is entering the final month of “withdrawal season,” when gas is taken out of storage to meet demand, with surprisingly low inventories. The government is expected to report Thursday that storage fell by about another 140 billion cubic feet last week. Citigroup estimates that the period from April through October, when gas stores are traditionally replenished, could start with inventories of 875 billion cubic feet—a little over half as much as a year ago. Some of the traditional levers for rebalancing gas supply and demand have become rusty after years of glut caused by the shale boom. For example, elevated prices between 2003 and 2008 forced industrial gas users to cut consumption. Today, gas-dependent industry is resurgent and gas-fired power plants have taken market share from […]