Travelers will notice that the mild daytime temperature declines as the week goes on, and there’s a strong chance of rain Tuesday, the Capital Weather Gang says.

The road crews that were off during the holiday weekend should be back at work by noon today. Metro has some major work scheduled for this weekend, but that will end the most disruptive rehabilitation activity for the year.

This week, and for the next few weeks, expect more traffic around the malls and shopping areas. Parking areas can be particularly dangerous, with people in a great hurry, whether in cars or on foot.

Speaking of seasonal activity, the annual lighting of the National Christmas Tree is scheduled for the Ellipse on Thursday — as usual — at the height of rush hour in downtown D.C.

Here are highlights of some of the obstacles that may affect your travels this week.

Constitution Avenue

Workers on the Constitution Avenue rehabilitation project are scheduled to put down pavement striping and signs, replace bus pads and sidewalks, install fencing, landscape and upgrade traffic signals between 23rd and 17th streets NW.

From 5:30 a.m. to 7 p.m. Monday through Wednesday, expect to find up to two lanes in each direction closed between 23rd and 15th streets. The exact location of the lane closings will vary each day.

From 7 p.m. to 5:30 a.m. weeknights, expect to find up to three eastbound lanes closed between 23rd and 17th streets for the replacement of bus pads. At the 17th Street intersection, where pavement repairs will be underway, expect to find one lane open in each direction.

National Tree lighting

The lighting of the National Christmas Tree, the annual holiday event that darkens the spirits of homebound commuters each December, is scheduled for 5 p.m. Thursday on the Ellipse, south of the White House.

The tree is beautiful, and the event is fun for families. The timing is ridiculous. It jams traffic for many blocks just as rush hour is beginning.

Beltway/Telegraph Road

The Woodrow Wilson Bridge project, which is rebuilding the Capital Beltway and the Telegraph Road interchange near the bridge in Virginia, is planning some lane closings on the Beltway.

From 9 p.m. to 5 a.m. Wednesday and Thursday nights, the two right lanes of the Beltway’s outer loop will be closed between the Eisenhower Avenue Connector and Telegraph Road for roadway construction. Project officials say they expect significant backups, so motorists should consider alternate routes.

During the same hours, the left lane of the inner loop is scheduled to close from Telegraph Road to the Eisenhower Avenue Connector to remove a barrier.

Southern Maryland road reopened

The Maryland State Highway Administration has reopened Route 234 (Budds Creek Road) over Allens Fresh Run. The road and a bridge, which provide an important link between Charles and St. Mary’s counties, were heavily damaged in the August and September storms.

The state replaced the bridge over Allens Fresh Run with a temporary span, set off slightly from the roadway. The highway administration says it is designing the permanent replacement, which now can be built without further closings of Route 234.

Route 29 ramp reopened

The Maryland State Highway Administration also has reopened the ramp from southbound Route 29 --Columbia Pike to eastbound Route 175 Little Patuxent Parkway-- in Columbia.

The ramp was closed in August so the state could resurface the eastbound and westbound Route 175 bridges over Route 29. Some remaining work, including painting the girders and installing pavement markings, should be done by spring.

Intercounty Connector

Maryland’s Intercounty Connector, which normally will be a toll road, is free all week following the opening of the new 10-mile segment between Georgia Avenue and Interstate 95. I’ve seen many people out taking their test drives, but it isn’t crowded. Remember the speed limit is 55 mph.

Tolling begins next Monday..

Anacostia Drive closing

The National Park Service says Anacostia Drive SE will be closed to all vehicular and pedestrian traffic from Good Hope Road SE to Nicholson Street SE from 10 p.m. Monday to 6 a.m. Tuesday.

Anacostia Freeway lane closings

The District Department of Transportation plans to close the northbound lanes of the Anacostia Freeway (I-295/DC 295 from 11th Street SE to Pennsylvania Avenue SE) on Wednesday and Thursday nights to erect girders on a new bridge over the freeway.

The closings are scheduled for 10 p.m. through 5 a.m. each night.

Detour: Cross the 11th Street Bridge onto M Street SE and then turn onto Ninth Street SE to head east on the Southeast-Southwest Freeway get back onto northbound I-295 via Pennsylvania Avenue SE and the Sousa Bridge.

Virginia Avenue meeting

The District Department of Transportation and Federal Highway Administration have invited the public to attend a second meeting to discuss plans to rehabilitate the Virginia Avenue Tunnel between Second and 11th streets SE.

CSX Transportation wants to replace the tunnel, which is more than a century old and has become one of the biggest railroad choke points along the East Coast. But the plan involves closing blocks of Virginia Avenue near the Southeast-Southwest Freeway for a lengthy period while the work is done.

Several design concepts have been developed, and they will be outlined at the meeting, scheduled for 6:30 to 8:30 p.m. Wednesday, inside Nationals Park, 1500 South Capitol St. SE. Navy Yard on the Green Line is the nearest Metrorail station. Free parking will be available in Lot C, at First and N streets SE, adjacent to he stadium. The session will begin with an open house, followed by a formal presentation at 7.

Metro weekend maintenance

There are two big projects scheduled for this weekend on Metrorail. On the Red Line, buses will replace trains between Glenmont and Rhode Island Avenue. On the Orange Line, buses will replace trains between Cheverly and Deanwood.