Some of the 1,500 workers on the 95 Express Lanes project are building up the earth to support a future flyover ramp to connect with the interstate’s median. (Robert Thomson/The Washington Post)

Commuters are starting what the Capital Weather Gang describes as summer’s most uncomfortably hot week, with very high temperatures and humidity.

The Mystics play in Verizon Center at 7 p.m. Tuesday. Baseball is in the All-Star break till Friday, when the Nationals start a series with the Dodgers at Nationals Park.

The biggest construction zone this summer is along Interstate 95 south of the Capital Beltway. Throughout the D.C. region, commuter traffic is into its summer slide, but hot spots remain. Stretches with the worst morning rush hour traffic include: The Beltway’s outer loop through Silver Spring, D.C. 295 South past Route 50, I-66 East near Route 50, I-295/D.C. 295 at the 11th Street Bridge, the George Washington Parkway through Rosslyn, I-395 near the 14th Street Bridge and I-66 West to Lee Highway.

Join me for a a special online discussion at noon Monday with two members of the Northern Virginia Transportation Authority.

HIGHLIGHTS: Metro schedule | NVTA online chat | Silver Line | D.C. freeway lanes | Route 32 paving | I-95 in Virginia | I-95 in Maryland | Cleveland Park plans | Ramp closing | Metro this weekend

Metro weeknights
After 10 o’clock each night through Thursday, Metrorail maintenance will delay service on all five lines by about 10 minutes. These are the work zones.

  • Red Line. Between Van Ness and Friendship Heights, and between Rhode Island Avenue and Takoma.
  • Blue Line. Between McPherson Square and Smithsonian, and between Van Dorn Street and Franconia-Springfield.
  • Orange Line. Between McPherson Square and Smithsonian.
  • Green/Yellow lines. Between Georgia Avenue and Fort Totten.

NVTA online chat

The newly empowered Northern Virginia Transportation Authority plans to make decisions this month about a first round of spending on transportation projects that could amount to $200 million.

The money is likely to go to a variety of road, transit, biking and walking projects across the region, but some transportation advocates favor spending on just a few projects that would have the highest possible impact on congestion.

What priorities would you set for the spending? I’ve invited two members of the authority’s board, Martin Nohe of Prince William and Chris Zimmerman of Arlington, to answer your questions. You can submit questions and comments now by using this link to the chat, then come back to the same link at noon for the discussion.

Silver Line in Tysons

It’s a very active summer in the Dulles Metrorail work zones along Routes 267, 7 and 123 where workers are finishing the first phase of the Silver Line. Here are a couple of highlights:

  • Watch for lane closings on Tysons Boulevard between Galleria Drive and Route 123 during the day for paving. Two lanes will be closed at night for waterline trench work.
  • Work on the Greensboro and Spring Hill Metro stations and along the sidewalks will require day and night lane closings in several spots on both sides of Route 7 and adjacent roads in Tysons.

D.C. freeway lane closings

The District Department of Transportation is closing lanes along I-695, the freeway south of Capitol Hill, to install new variable message signs. Watch for traffic barrels and concrete barriers.

The first phase is set to begin Saturday and continue through Aug. 10. The left-most lanes on both sides of the interstate near the South Capitol Street exit will be closed. To set up equipment, an additional left lane will be temporarily closed between 2 a.m. and noon Saturday and again between 10 p.m. and 5 a.m. July 25 and 26, if the work schedule holds.

A second phase will start on July 27 and continue through Aug. 11. This phase will close the right lane on the westbound side approaching the Third Street Tunnel. To set up equipment for this, an additional right lane will be temporarily closed starting at 10 p.m.  July 27 through eight o’clock the following morning and between 2 a.m. and noon, and again between 10 p.m. and 5 a.m. July 29.

In mid to late August, a third phase will close the right lane on the eastbound side from the South Capitol Street exit to Sixth Street SE.

Night paving on Route 32

The Maryland State Highway Administration is closing lanes along a mile of Route 32 north of I-70 in Howard County for paving. The work is scheduled to be done by fall.

Meanwhile, watch for single-lane closings and lane shifts between 7 p.m. and 5 a.m. on weeknights

I-95 in Virginia

The 95 Express Lanes construction zone, stretching from just inside the Capital Beltway in the north to Garrisonville Road in the south, includes several different work environments. In the north, today’s High Occupancy Vehicle lanes are being converted into high-occupancy toll (HOT) lanes. To the south, beyond the HOV zone, new HOT lanes are being built.

Much of the work is in the I-95 median, where the new lanes will open, but there’s also considerable activity along the shoulders. Throughout the summer, watch for:

  • Extensive lane closings and delays at off-peak hours day and night.
  • Occasional full closings of I-95 and overnight detours.
  • Slow-moving trucks entering and leaving the work zone in the median.
  • Reduced access to shoulders.

Drivers already encounter these conditions, and another major disruption is scheduled this coming weekend. The express lanes project is scheduled to close all lanes of I-95 South near Telegraph Road Bridge in Quantico on Friday and Saturday nights so that workers can place steel beams for the new Telegraph Road bridge over the southbound lanes.

Starting at 9 p.m., crews will close a southbound lane. After midnight, all the southbound lanes will be closed and drivers will be detoured east from the Russell Road exit to Route 1, then south so they can return to I-95 at Garrisonville Road. The detour will add about 25 minutes to trips.

I-95 in Maryland

The Maryland State Highway Administration is demolishing the bridge over I-95 at Van Dusen Road, south of exit 33 in Laurel. The work should be done by late summer. During the current phase, watch for closings of the two right northbound lanes on I-95 starting at 8 p.m. Saturdays through Thursdays. The lanes will reopen by six o’clock each morning.

Once work is done above the two right lanes, crews will close the two left lanes.

SHA and state police will sometimes stop all traffic on northbound I-95 for no more than two 15 minute to 30 minute intervals between midnight and 4 a.m. to remove steel beams.

Once the work is done on the northbound side, the process will be repeated on the southbound side.

The SHA noted that more than 185,000 vehicles use this section of I-95 daily. If traveling during the overnight work hours, consider north-south alternatives such as Routes 1 and 29, or the Baltimore-Washington Parkway (no heavy trucks).

Cleveland Park plans

The District Department of Transportation has invited the public to share ideas for improving all forms of travel in Cleveland Park.

The session is scheduled for Wednesday from 6:30 p.m. to 8:30 p.m. in the community room at the Second District police station, 3320 Idaho Ave. NW.

Ramp closing

This weekend, the Maryland State Highway Administration plans to again close the ramp from westbound Route 50 to southbound Route 301. The closing, to improve the ramp surface, is set to begin Friday at 9 p.m. and end Monday at 5 a.m.

Metro this weekend
[The Green Line information has been updated.]
All stations will be open this coming weekend, but work zones will change the train schedules on the Red, Orange and Green lines between 10 p.m. Friday and the rail system’s midnight closing Sunday.

  • Red Line. Between Shady Grove and Glenmont, trains are scheduled to operate every 20 minutes through the weekend. But between 9 a.m. and 9 p.m., additional trains will be operating in certain zones, so between Shady Grove and Farragut North, and also between Glenmont and Judiciary Square, trains should reach the platforms every 10 minutes.
  • Orange Line. On Saturday, every other train will operate between Vienna and Stadium-Armory only. So in that zone, Orange Line trains should arrive every 12 minutes. work zone at Minnesota Ave & Deanwood stations, every other Orange Line train will operate between Vienna & Stadium-Armory only. Because of a work zone to the east of there, passengers will have longer waits between trains at Minnesota Avenue, Deanwood, Cheverly, Landover and New Carrollton. On Sunday, trains will operate every 20 minutes between the ends of the line at Vienna and New Carrollton.
  • Green Line. Green Line trains will operate every 20 minutes throughout the weekend. Trains will be sharing a track in a work zone between College Park and Fort Totten.