Sting and Shaggy are teaming up to host and headline One Fine Day, a Sept. 9 music festival held at the Mann Center in Philadelphia's Fairmount Park. Performers include Thundercat, Tank and the Bangas, Koffee, G. Love & Special Sauce, Kes, Flor de Toloache and Giordana Angi. Presale tickets will be available Tuesday, May 16, and general tickets go on sale Friday, May 19.