What are you doing tonight? Is it celebrating the good weather that’s cracked DC open to fun summer-style activities like fresh Southern rock concerts? If that’s not what you’re doing, rethink your Friday night plans. Blackberry Smoke mixes “elements of gospel, bluegrass, arena rock, soul and more than a touch of outlaw country” that boils together like the best homemade preserves you’ve ever tasted. And they’re playing the Fillmore tonight.