Fans watch Grouplove perform at the BottleRock Napa Valley music festival, in Napa, Calif., on Friday, May 27, 2016. (Anda Chu/Bay Area News Group)
Buddy Guy performs at the BottleRock Napa Valley music festival, in Napa, Calif., on Friday, May 27, 2016. (Anda Chu/Bay Area News Group)