Natural gas prices rose to a 2 1/2-month high Thursday, flipping up from losses after data showed a below-average storage addition last week. The U.S. Energy Information Administration said natural-gas stockpiles grew by 62 billion cubic feet last week. While that is more than the 60 bcf expected by forecasters surveyed by The Wall Street Journal, it is lower than both last year’s addition and the five-year average addition for this week of the year. That suggests smaller supply or greater demand compared with a year ago. While that might often be a secondary concern to how the weekly data compared with expectations, right now traders are eagerly looking for reasons to buy, said Teri Viswanath, managing director of natural gas at PIRA in New York. Many expect a drop in drilling work and growing demand for gas-fired power and heat to erase a long-standing glut in the market. […]