Metro is warning Blue and Yellow Line riders to add a half hour to their travel time this weekend.
Track work, starting at 10:00 tonight and ending at midnight on Sunday, will force trains to single-track through parts of the system.
Metro says riders should expect trains to run about every 30 minutes on both lines.
As a reminder, those driving into the District may also face delays this weekend. Chain Bridge will be closed to all traffic starting at 9:00 tonight.