Summer is for location scouting! Over the past month, I've found two great locations for outdoor sunset shots.
The Anacostia River Trail at the Melrose Skate Park
This spot has beautiful light at sunset and several awesome spots for photos. Bonus is that it's super accessible from the Brookland neighborhood!
Kingman and Heritage Islands
Another awesome spot with river and sunset views--just make sure you wear bug spray! Parking is also easy since the entrance is at one of the RFK stadium lots.