SARA WATKINS On her second solo album, Sun Midnight Sun, Watkins expands her sunny West Coast folk and Americana into a moodier mix of country, Celtic, bluegrass and pop. The outing may not be as straight roots-leaning as her work with her former band Nickel Creek, but she continues her adept explorations on guitar and fiddle, caressing the strings or spewing toe-tapping energy as the song beckons. Watkins’ versatility, honed over the past decade of writing and performing with a diverse crowd of music makers, and lifted by her sweetly haunting voice, clearly gives her staying power. Opening for Jackson Browne. $49.50-$84.50. 8 p.m. Belk Theater.