* Front month below Wednesday's 21-month high * Weather outlooks remain mixed for May * Nuclear power plant outages remain below normal * Coming Up: EIA natgas storage data 10:30 a.m. EDT (1430 GMT By Eileen Houlihan NEW YORK, May 2 (Reuters) - U.S. natural gas futures edged higher early on Thursday, boosted by continued near-term cool weather in the middle of the nation and expectations for another light weekly inventory build when data is released later Thursday. A long cold winter put a huge dent in inventories, and lingering cool weather this spring has led to a slow start to the injection season. Most traders and analysts expect weekly data from the U.S. Energy Information Administration to show a build of about 28 billion cubic feet when it is released at 10:30 a.m. EDT (1430 GMT), a Reuters poll showed. Stocks rose 31 bcf during the same week last year and on average over the past five years have gained 67 bcf that week. Still, most traders expect the onset of milder spring weather in the coming weeks to finally curb any late-season heating demand before heavy cooling loads kick in. As of 9:04 a.m. EDT (1304 GMT), front-month June natural gas futures on the New York Mercantile Exchange were at $4.346 per million British thermal units, up 2 cents, or less than 1 percent. The contract rose as high as $4.444 on Wednesday, its highest mark since late July 2011, according to Reuters data. The latest National Weather Service six to 10-day forecast issued on Wednesday called for above-normal temperatures for about the western third of the country and in northern New England and below-normal readings for most of the remainder of the country. Nuclear plant outages totaled 20,400 megawatts, or 20 percent of U.S. capacity, down from 22,800 MW out on Wednesday, 22,900 MW out a year ago and a five-year average outage rate of 22,200 MW. ANOTHER LIGHT INVENTORY BUILD EXPECTED Last week's EIA gas storage report showed domestic inventories rose the prior week by 30 bcf, below Reuters poll estimates for a 32 bcf build, the year-ago gain of 43 bcf and the five-year average build of 50 bcf for that week. Inventories also started the injection season about three weeks later than expected due to the unusually cold spring and stocks, at 1.734 trillion cubic feet, are nearly 32 percent below last year and more than 5 percent below the five-year average. EIA data on Tuesday showed gross natural gas production in February climbed for the first time in three months. Output rose to about 1.27 bcf per day, or 1.8 percent above the same month last year, after dropping below year-ago levels in January for the first time since 2010. The report dimmed prospects that record high production would slow anytime soon despite Baker Hughes gas drilling rig data last week that showed the rig count dropped to a 14-year low.