I went down to DC's tidal basin to take some pictures this morning. I knew the blossoms weren't out yet, but was going to start there and walk over to the Smithsonian to take some more shots.
The picture above shows the current state of the buds, so I'm sure they'll be out pretty soon.
To track it, the National Park Service maintains a webcam (mounted at the Jefferson Memorial) showing current status. I'm hoping Sunday morning, but not certain about that. Regardless, my plan is to be at the tidal basin that morning, fingers crossed.