Updated at 6:48 p.m.
Then a train at Union Station had a problem with its door at 5:20, causing the delays to get worse.
Ten minutes later, another train had a door problem, this one at Farragut North. All passengers were told to exit the train.
And about 10 minutes after that, passengers of a second train were told to exit onto the platform at Farragut North as well. This train had a brake problem.
Just one minute later, passengers were booted off a train one stop away, at Dupont Circle, because it needed service.
And five minutes later, yet another train offloaded, this one at Metro Center.
Trains were single-tracking between Judiciary Square and Farragut North, a four-station stretch in the busy heart of downtown D.C., but are now running on both tracks.
Still, riders should expect some very crowded stations.