* Front month remains above recent 3-month low * Near-term mild weather to turn cold again next week * Nuclear outages running well above normal levels By Eileen Houlihan NEW YORK, Feb 12 (Reuters) - U.S. natural gas futures seesawed between negative and positive territory early on Tuesday, with a bias to the upside amid prospects for more cold weather next week after some milder conditions in consuming regions this week. Above-normal nuclear power plant outages were helpin