As we head into the last weekend of winter, with outdoor activities picking up, remember to watch for more walkers and bikers. Sunday will be the better of the two days for such activities, the Capital Weather Gang says. There’s a good chance of rain Saturday. The NCAA basketball tournament will draw a crowd to the Verizon Center on Saturday. This is the last weekend of Metro track work for a while, because the springtime crowds are about to arrive in the D.C. area for the Cherry Blossom Festival.

Metro weekend delays

Orange Line: There will be no train service between East Falls Church and West Falls Church stations from 10 o’clock Friday night through the rail system’s midnight closing Sunday. This is the same service disruption that occurred last weekend, for the same reason: The Dulles Metrorail project is working on what will eventually become the connection between the new line and the Orange Line.

During the weekend work, both stations will remain open, and Metro will operate free shuttle buses between them to link the two segments of the Orange Line. But this will add half an hour to a journey between the stations.

At East Falls Church, riders will find the shuttles at bus bays C and D. At West Falls Church, they will be found at the bus loop outside the Kiss & Ride by the south entrance to the station.

Red Line: From 10 p.m. Friday to the midnight closing Sunday, trains will share a track between Forest Glen and Glenmont. Metro will be replacing rail switches outside the Wheaton Station. Trains also will share a track between Twinbrook and Grosvenor while workers repair the platform at White Flint Station.

On Saturday and Sunday, trains are scheduled to leave the ends of the line at Shady Grove and Glenmont about every 26 minutes. From 9:30 a.m. to 9:30 p.m. each day, there will be more service through the interior part of the line. Trains between Grosvenor and Silver Spring are scheduled to leave about every 13 minutes.

Blue/Yellow lines: From 10 p.m. Friday through closing time Sunday, Blue Line trains will share a track between Stadium-Armory and Addison Road. Workers will be repairing the slabs underneath the rails in that area.

During the same time, Yellow Line trains will share a track between Pentagon City and L’Enfant Plaza and Blue Line trains will share a track between Pentagon City and Arlington Cemetery. Workers will be welding new rails and installing cables that will eventually improve cellphone service.

On Saturday and Sunday, all Blue and Yellow Line trains will operate about every 20 minutes apart. The Yellow Line will be operating between Huntington and Mount Vernon Square. Normally, the trains would continue north to Fort Totten during the weekend.

Beltway bridge reopening

The Idylwood Road bridge, between Interstate 66 and Route 7 south of Tysons Corner, reopened Friday morning after rush hour. The bridge over the Capital Beltway was rebuilt as part of the High Occupancy Toll lanes project.

The new two-lane bridge, which does not have an interchange with the Beltway but is used to link neighborhoods, is slightly wider than the old one to accommodate pedestrians and bicyclists.

More parking on H Street NE

The D.C. Department of Transportation plans to reopen parking on the south side of H Street NE between Third and Eighth streets after the paving and lane striping are done Saturday, weather permitting. The department has been rebuilding H Street and installing tracks for a future streetcar.

Union Station entrance closing

The Union Station entrance at Massachusetts Avenue NE will close at 8 p.m. Sunday so that Metro can fix the station manager’s kiosk on the mezzanine. The entrance will reopen at 5 a.m. Monday. During the work, the entrance at First Street NE will remain open.

Forestville Road/Beltway

On Monday night, the Maryland State Highway Administration plans to close the Forestville Road Bridge over the Capital Beltway as part of a $1.6 million rehabilitation project. Crews will close the roadway at midnight to replace a steel beam, and it should be reopened by 5 a.m. Tuesday. The exit lane from the Beltway’s inner loop to Forestville Road (Exit 9) also will be closed. All travel lanes on the Beltway will remain open. Traffic will detour onto Pennsylvania Avenue and back to Forestville Road during the ramp closing.

Constitution Avenue reconstruction

The National Park Service is going to begin preparations this coming week for a big project on Constitution Avenue that is likely to create traffic delays for many months.

The first signs of this project, between 15th and 23rd streets NW, will include temporary closings of the parking lanes during off-peak hours. The the project will really become active the week of April 10, the park service says. The rebuilding of the roadway will occur throughout the day, overnight and on weekends. It will be done a block at a time, closing up to two lanes in each direction, until completed in early 2012.

11th Street Bridge

The D.C. Department of Transportation may close lanes during off-peak travel hours on the 11th Street Bridge spans, ramps, portions of the Southeast-Southwest Freeway, Interstate 295/DC 295 and local streets starting Wednesday and continuing through June 22. Work on the two spans that will carry highway traffic is scheduled to be done at the end of the year.

Circulator route changes

The D.C. Circulator’s Web site says that the Smithsonian-National Gallery route “resumes in April 2011,” but that’s very unlikely. The route around the National Mall is the least successful of the Circulator routes and is likely to be discontinued.

Overall, the Circulator service has been a great success. With more than five million riders in 2010, it is now the fourth-largest bus service in the D.C. region, after Metrobus, Montgomery County’s Ride On and the Fairfax Connector. But the Mall route, designed to operate in the tourist season, was averaging 10 riders an hour. The D.C. Department of Transportation is interested in shifting the money it would have spent on the Mall route to extend the operating hours of the Union Station-Navy Yard line.

Metro suspending weekend maintenance

But only for the three weekends after this, a time period that will coincide with the heavy ridership during the Cherry Blossom Festival. Work will continue on the escalators and elevators.