At the start of her set, a rainbow painted the sky. Ms. Hale-McGill, who hails from Meraux, just outside New Orleans, is an independent artist who blends hip-hop and gospel.

Mayor LaToya Cantrell issued a proclamation to recognize June 11 as "Back That Azz Up Day," in celebration of the 1999 hip-hop hit song and its music video released by New Orleans' one-and-only ...