Tribune Media Co. said its WGN America is debuting on cable television systems in Chicago, Boston, Philadelphia, Seattle and Washington, D.C., starting today, as it begins converting from a superstation to a cable network. Tribune said these first launches are occurring on Comcast systems under agreements with the nation's largest cable operator. More launches and conversions will be happening on distributors this month and throughout 2015, Tribune said.

The conversion -- which means obtaining license fees under agreements from distributors instead of royalty payments -- follows Tribune's investment in original content on WGNA, including new series Salem and Manhattan, both of which have been renewed for second seasons in 2015. The network's first two unscripted series, Wrestling with Death and Outlaw Country will premiere on Tuesday, Jan. 13, and Tuesday, Feb. 24, respectively. WGNA also is adding syndicated dramas Person of Interest, Elementary and Blue Bloods in September 2015.

More as the story develops.