* Front month remains above recent 3-month low * Colder weather set to return this weekend, next week * Nuclear outages running well above normal levels * Coming Up: CFTC futures trade data Friday By Eileen Houlihan NEW YORK, Feb 15 U.S. natural gas futures ended lower for a second straight session on Friday, closing out the week down nearly 4 percent ahead of the Presidents Day holiday weekend. Despite forecasts that cold weather will return to consuming regions over the weekend and next week and that nuclear power plant outages will be above normal, bloated inventories and the approaching end of winter added weight to the downside. Thomson Reuters Natural Gas Analytics data showed heating degree days would remain above normal for the next two weeks, with some overnight models showing upward changes in demand over the first two weeks of March. Degree days are a measure of departure in the mean daily temperature from 65 degrees Fahrenheit (18 degrees Celsius) and are used to estimate demand to heat or cool homes and businesses. "Trading after yesterday's sell-off continues to suggest that the bulls are getting tired of waiting for a winter price surge and are gradually in the process of moving to the sidelines," said Energy Management Institute's Dominick Chirichella. Front-month March natural gas futures on the New York Mercantile Exchange slid 1 cent to settle at $3.153 per million British thermal units, after trading between $3.125 and $3.194. The contract slid 11.9 cents, or nearly 4 percent, on the week. The front month contract, which tumbled more than 4 percent Thursday following the release of bearish weekly inventory data, hit a 6-1/2 week high of $3.645 in late January after touching a more than a three-month low of $3.05 in early January. NYMEX floor trading will be closed Monday for the Presidents Day holiday, but electronic trading will continue. Traders noted that futures-only volume for trade-day Thursday, released on Friday, exceeded 531,500 contracts, the highest so far this year, topping the 529,036 contracts traded on Feb. 7. In the cash market, gas for delivery through Tuesday at the NYMEX benchmark Henry Hub in Louisiana fell 11 cents to average $3.19, with late deals easing to 9 cents over the front month, from deals done late Thursday at a 12-cent premium. Gas on the Transco pipeline at the New York citygate , however, jumped nearly $10 on the colder weekend forecast, to $14.75. Forecaster MDA Weather Services, in its one- to five-day outlook, called for an "unsettled, stormy pattern" with normal or below-normal temperatures over the nation. Its six- to 10-day forecast, as well as the latest National Weather Service six- to 10-day forecast issued on Thursday, called for normal or below-normal temperatures for most of the country. Nuclear outages totaled 14,100 megawatts, or 14 percent of U.S. capacity, unchanged from Thursday but up from 12,100 MW out a year ago and a five-year average outage rate of about 8,800 MW. ANOTHER BELOW-AVERAGE STORAGE DRAW Data from the U.S. Energy Information Administration on Thursday showed total domestic inventories fell last week by 157 billion cubic feet to 2.527 trillion cubic feet. Most traders viewed the report as bearish, noting the draw came in below Reuters poll estimates for a 162 bcf drop and was under market expectations for a third straight week. While stocks are nearly 10 percent below last year's record levels, they are 16 percent above the five-year average level for this time of year. Early withdrawal estimates for next week's inventory report range from 118 bcf to 154 bcf, below the 155 bcf pulled from storage during the same week in 2012 and possibly below the five-year average decline for that week of 140 bcf. If drawdowns for the rest of winter match the five-year average pace, inventories will end March at 2.076 tcf, about 20 percent above normal but 16 percent below last year, when stocks finished a very mild heating season at a record high 2.48 tcf. DRILLING DECLINES, PRODUCTION FAILS TO SLOW Baker Hughes data on Friday showed the gas drilling rig count fell for the fifth time in six weeks, dropping by four to 421. But while the gas rig count is hovering not far above the 13-1/2 year low of 413 reported three months ago, production has shown no significant sign of slowing. Producers have curbed dry gas drilling, but the associated gas produced by more profitable liquids-rich wells has kept gas flowing at or near a record pace.