Saturday, July 5 @ Briggs & Stratton Big Backyard, 10 p.m.
April’s Lights Out is the perfect example of her album-by-album progress from collegian folk to genre-absorbing anthemic pop. It includes everything from upbeat ballads to infectious synth pop, aggressive guitar riffs and one of the catchiest singles on adult contemporary radio, “Girls Chase Boys.” Seven years bolder, Michaelson is still the type of musician more at home on “Grey’s Anatomy” than many of the series regulars (her songs are on at least 16 episodes of the hospital soap, including this season’s finale). But she has fully developed into one who won’t get swallowed whole by an energetic Summerfest crowd. Michalson slowly found a way to be both of those things. She is, as they say, all that.