NEW YORK, June 26 (Reuters) - U.S. natural gas futures edged higher, backed by a slightly warmer extended weather outlook and some technical buying ahead of the July contract expiration later on Wednesday. Despite Tuesday's break of support, many technical traders agreed the market was overbought and due for a short-covering bounce after sliding 8 percent in the previous four sessions, the biggest four-day drop for front futures in seven weeks. While the overnight outlook for the six-to-15-day period did turn slightly warmer, many traders see only limited upside potential without a sustained, broad-based heat wave, particularly with inventories comfortable and gas production still at or near a record high. At 9 a.m. EDT (1300 GMT), front-month July gas futures on the New York Mercantile Exchange, which expire later on Wednesday, were up 3 cents at $3.677 per million British thermal units after trading between $3.646 and $3.712. The front contract posted a 3-1/2-month low of $3.645 on Tuesday. Heat remains focused in the West for the next two weeks, but private forecaster MDA Weather Services noted that the Northeast was slowly trending warmer, with higher temperatures expected to stretch across northern tier states late in the period.