US natural gas prices fell to $3.16 per million British thermal units on Friday as traders took profits after prices reached a 13-week high in the previous session. The earlier rally followed an unexpected mechanical issue at TC Energy’s Columbia Gas Transmission pipeline in Appalachia, which led the operator to declare force majeure and triggered the market’s largest single-day gain since January. The market remains supported by LNG demand, with average gas flows to the nine major US export plants rising to 17.8 billion cubic feet per day in September from 17.2 bcfd in August, despite the planned maintenance shutdown of Berkshire Hathaway Energy’s 0.8-bcfd Cove Point facility. EIA data showed inventories increased by 53 billion cubic feet in the week ended September 18, narrowing the storage surplus over the five-year average to 95 bcf from 118 bcf a week earlier. Hot weather boosted cooling demand. September production remained near record levels at an average 112.8 bcfd, although daily output has been declining mainly because of reductions in Louisiana and West Virginia. Earlier market data had placed Lower 48 production at an 11-week low of 108.4 bcfd, while forecasts called for mostly normal weather through October 9.