This post has been updated.

The Capital Weather Gang thinks this weekend could be a highlight of the month of May and a great time to travel around the D.C. region. But be wary of work planned for the roads and rails.

A wooden beam is lowered into place for a piece of machinery to be moved on the 11th Street Bridge project on June 29, 2011 in Washington, D.C. (Mark Gail/The Washington Post)

Join me at noon Monday for our weekly online discussion of your traffic and transit concerns. You can submit a question or comment in advance. Sunday’s Post Commuter page will include advice for bicyclists and drivers about sharing the roads.

Metro weekend delays

Work on the Red, Orange and Blue lines starts at 10 p.m. Friday and continues through the rail system’s midnight closing Sunday. The impact on riders comes from trains sharing tracks to get around work zones. There are no station shutdowns scheduled for this weekend.

See our guide to upcoming Metro weekend shutdowns.

Red Line: Trains will share a track between Takoma and Forest Glen, and between Van Ness and Dupont Circle. They will operate every 24 minutes between the ends of the line at Shady Grove and Glenmont. Allow about 20 minutes of for extra travel time, Metro said.

Between 9 a.m. and 9 p.m. Saturday and Sunday, more trains will operate in downtown D.C. between Farragut North and New York Avenue. In that zone, trains should arrive about every 12 minutes, Metro said.

Orange Line: Trains will share a track between Eastern Market and Cheverly. They are scheduled to leave the ends of the line at Vienna and New Carrollton about every half hour. Add about 20 minutes to normal travel times, Metro said.

Blue Line: Trains will share a track between Eastern Market and Addison Road. They are scheduled to leave the ends of the line at Franconia-Springfield and Largo Town Center about every half hour. Add about 20 minutes to normal travel times.

I-295/DC 295

Stay away from the northbound Anacostia Freeway near the 11th Street Bridge for about 24 hours starting at 8 p.m. Friday. The District Department of Transportation plans to close the northbound lanes between Howard Road and Pennsylvania Avenue SE.

The closing will allow workers to shift northbound traffic onto its final alignment in the vicinity of the bridge rebuilding project.

The lanes will shut down in sequence beginning with a single lane closing at 8 p.m. All the lanes will be closed by 10 p.m. Project managers hope to get them reopened by 8 p.m.

If you absolutely have to go through this area, this is the detour to follow: Traffic will be directed onto the inbound 11th Street Bridge, then to westbound M Street SE. From there, drivers can reach the eastbound Southeast-Southwest Freeway using the Ninth Street SE entrance ramp. From there, head for eastbound Pennsylvania Avenue, cross the Anacostia River and make a left at the light to return to northbound DC 295.

Southeast-Southwest Freeway

On the west side of the Anacostia River near the 11th Street Bridge project, the District Department of Transportation has permanently closed the Eighth Street exit ramp from the westbound Southeast-Southwest Freeway.

This is the ramp for freeway traffic coming from Pennsylvania Avenue and heading for the Marine Barracks and Eighth Street SE. The exit to Eighth Street from the inbound 11th Street Bridge will remain open.

Bike DC

Street closures will begin at 5 a.m. Sunday and continue through approximately noon for Bike DC, a community bike riding event. According to the city, the race and road closures will use the following course:

• 3rd St between Pennsylvania Ave NW and Maryland Ave SE

• North on 3rd Street NW

• Left on Pennsylvania Avenue NW

• Right on 15th Street NW

• Left on Pennsylvania Avenue NW

• Right on 21st Street NW

• Left on K Street NW

• Under Washington Circle

• Right on Rock Creek Parkway

• U turn on Rock Creek Parkway before Beach Drive, NW

• South on Rock Creek Parkway

• Left on K Street NW

• Under Washington Circle

• Right on 21st Street NW

• Left on Pennsylvania Avenue

• Right on 19th Street NW

• Right on E Street NW (E Street Expressway)

• Straight on I-66 Ramp at 20th Streeet NW

• Across Theodore Roosevelt Bridge into Virginia, where the race will continue on GW Parkway

• Across the Theodore Roosevelt Bridge back into the District on the E Street Expressway.

The city reports in addition to these closures, both northbound lanes of the George Washington Memorial Parkway in Virginia will be closed from the Memorial Bridge up to the Chain Bridge exit.

Annapolis triathlon

Many streets will be closed and parking will be restricted Saturday morning in the Annapolis Historic District and in West Annapolis for the TriRock Annapolis Sprint Triathlon.

Streets along the triathlon route will be closed starting at 7 a.m. as the first participants approach, then will reopen as the stragglers pass and crews clean up.All streets should reopen by 10:45 a.m., except for the lower part of Prince George Street at Annapolis Harbor, which is scheduled to reopen at 6 p.m. The Naval Academy Bridge will reopen at 10 a.m.

Free parking will be available at the Bladen Street garage beginning at 6 p.m. Friday.

College Avenue will remain open from Prince George Street to St. John’s Street throughout the race, providing access to Rowe Boulevard and Calvert Street, across Rowe.

See a map of the street closings on this page of the triathlon Web site.

Canal Road

Watch for lane closings Friday night on Canal Road at Arizona Avenue NW. The National Park Service says workers will be installing a safety net under the pedestrian bridge over Canal Road in that area. The contractor hopes to finish the job in one night.

Expect to find two lanes closed between 9 p.m. and 5 a.m. Flaggers will direct traffic into one open lane at a time.

Road closing in Frederick

The Maryland State Highway Administration plans to temporarily close East South Street between Franklin Street and Monocacy Boulevard from Friday night after rush hour till 5 a.m. Sunday. The East South Street/Monocacy Boulevard intersection also will be closed.

Drivers heading south on South Street will be detoured to Franklin Street to East Patrick Street to Monocacy Boulevard to westbound Interstate 70 to the interchange at Buckeystown Pike, then to eastbound I-70 to South Street/Reichs Ford Road.

Traffic going north on Reichs Ford Road will be detoured onto eastbound I-70 to East Patrick Street to Monocacy Boulevard.

Motorists heading east on I-70 to South Street or the Frederick Fairgrounds should use the East Patrick Street exit (Exit 56) rather than the South Street exit (Exit 55), the SHA said.

The work is part of a project to widen I-70 at South Street and replace the I-70 bridges over South Street in Frederick. The project should be done in the summer of 2013.

Bethesda bike racks

Katherine Shaver reports that a hundred more bike parking spaces will be installed soon in downtown Bethesda. The first two new racks, providing parking for about 20 more bikes, will be available next Friday at the corner of Woodmont and Bethesda avenues, and all the racks should be installed by mid-June.

Bike to Work Day

Next Friday also is Bike to Work Day, your annual chance to see what it’s like to bike to work in the D.C. region, accompanied by a support team.

More than 10,000 commuters will organize themselves into convoys at 58 designated gathering points and make the trip to work. Cyclists can register to get a free Bike to Work Day T-shirt at these pit stops, along with free food and drink and a chance to win a bicycle or other prizes.

To register online and get more details about the pit stops, visit

Fairfax County Parkway/Fair Oaks

Look for continued delays and detours at the intersection of the Fairfax County Parkway and Fair Lakes Parkway this coming week, the Virginia Department of Transportation said.

The work that began this week is scheduled to continue. From 9 p.m. to 5 a.m. weeknights, workers will be placing beams for the bridges that will carry traffic over Fair Lakes Parkway and Monument Drive.

Drivers heading to the Fairfax County Parkway from Monument Drive will be detoured to West Ox Road.

The rebuilding of the intersection is scheduled to be done in 2013. It will widen more than three miles of the Fairfax County Parkway and separate local and parkway traffic through this intersection area.

Dulles Access Highway

Drivers heading east from Dulles International Airport late at night this coming week will find the Dulles Access Highway closed. The eastbound traffic will be diverted onto the Dulles Toll Road and drivers will pay the $1.50 toll at the main toll plaza.

It’s very unusual for traffic to be diverted from the free airport access road to the toll-paying lanes. But the Dulles Metrorail project announced that the closing, which began this week, is necessary to complete the last part of the flyover bridge that will bring the track for the new Silver Line out of Tysons Corner and into the middle of the Dulles highway.

The closed portion of the Dulles Access Highway will extend from Centreville Road to just past the main toll plaza. The closing will be imposed from 9 p.m. to 5 a.m. Sunday through Thursday nights and from 9 p.m. to 7 a.m. Friday night.

Sherman Avenue NW

This coming week, the District Department of Transportation is going to temporarily shift the traffic pattern on Sherman Avenue NW between Fairmont and Girard streets. Traffic will be moved to the east side of the avenue to make room for reconstruction the west side that’s part of the Sherman Avenue Streetscape project.

Drivers will have one northbound and one southbound through that area during the construction.