8:30 A.M. Update:
All MARC Penn Line trains heading in and out of Washington are being delayed due to signal and switch problems.
MARC Penn Line train 421 is expected to leave Baltimore 15 to 20 minutes late.
8:15 A.M. Update:
MARC Penn Line train 410 is expected to run 15 to 20 minutes late due to the signal and switch problems near Washington.
8 A.M. Update:
All MARC Penn Line trains traveling in and out of Washington are being delayed due to signal and switch problems just outside of Washington.
7:50 A.M. Update:
A disabled vehicle on the outer loop of the Beltway at I-66 is blocking the right shoulder.
7:35 A.M. Update:
Again, a water main break in Arlington has closed South Courthouse Road between 6th and 8th streets. Expect the street closure to remain for the next couple of hours and avoid that area.
7:15 A.M. Update:
MARC Brunswick Line train 880 will run with one fewer cars than normal this morning, so watch out for crowding on the remaining cars.
7 A.M. Update:
The debris on westbound Sandy Spring Road/MD 198 at I-95 has been cleared.
6:45 A.M. Update:
I-66 East is quite congested at Chain Bridge Road.
6:30 A.M. Update:
Debris on westbound Sandy Spring Road/MD 198 at I-95 could lead to delays there.
6:25 A.M. Update:
A water main break in Arlington has closed South Courthouse Road between 6th and 8th streets. The street will remain closed for the next few hours, so seek alternate routes.
ART routes 42 and 45 will be detoured due to the water main break, but no stops will be missed, according to Arlington Transit.
Good morning, commuters! We’ll be keeping an eye on the roads and rails this morning, reporting any delays or issues — and we will need your help.
If you hear about any congestion, delays or problems, tell us in the comments section below or by tweeting @drgridlock.
The week kicks off with oppressive, sweltering heat, according to the Capital Weather Gang.
Click here to receive e-mail alerts for major traffic and transit issues.