Reagan National Airport station will be closed this weekend for work on the Blue and Yellow lines. (John McDonnell — The Washington Post)

Crews will be working on all five Metro lines this weekend, but the biggest disruptions will be to rail service on the Blue and Yellow lines in Virginia, where buses will replace trains through a work zone. On the Red, Orange and Green lines, schedules will be adjusted, but trains will operate all the way.

The schedule changes will begin at 10 p.m. Friday and continue through the end of service at midnight Sunday.

Blue Line. Workers will make repairs and upgrade equipment between Braddock Road and Pentagon City. The Reagan National Airport and Crystal City stations will be closed. Free shuttle buses will replace trains between Braddock Road and Pentagon City.

An express bus will stop at Braddock Road and Pentagon City, adding about 15 minutes to normal travel time. A local bus will include stops at the National Airport and Crystal City stations, adding about 20 minutes to normal travel time, the transit authority said.

Outside the work zone, trains will operate on their normal weekend schedule, every 12 minutes during the day and every 15 to 20 minutes at night.

The time for the last train of the night from Franconia-Springfield will be 22 minutes earlier than normal so the train can make its shuttle bus connection. The last train times on Friday and Saturday nights will be 2:07 a.m. The last train on Sunday night will leave Franconia-Springfield at 11:07.

Yellow Line. The work zone, station closings and shuttle bus operations for the Yellow Line are the same as those for the Blue Line. Outside the work zone, Yellow Line trains will operate on their normal weekend schedules, but northbound service will end at Mount Vernon Square, rather than Fort Totten. Switch to the Green Line at Mount Vernon Square to continue north.

To make the shuttle bus connection, the last train of the night from Huntington will leave at 2:12 a.m. on Friday and Saturday nights, and at 11:12 p.m. on Sunday.

Green Line. Crews will work on the tracks between Fort Totten and Prince George’s Plaza. All along the line, trains will operate every 16 minutes.

Red Line. Trains will operate on their regular weekend schedules with one exception. The trains that normally begin or end their runs at Grosvenor will instead use the next station south, Medical Center, as their terminal. So riders traveling to or from the Grosvenor station who usually have a one-seat trip will need to switch trains at Medical Center.

Orange Line. Workers are rebuilding platforms at the Minnesota Avenue and Deanwood stations. Other jobs involve fixing rail ties and insulators. Trains will operate every 20 minutes all along the line.