All morning Pepco has been doing some utility work on Northbound Wisconsin Avenue (MD-355) between Montgomery Avenue and East-West Highway. They have closed the two right lanes, only a single lane gets through on the left.
As you might imagine, this is causing a significant traffic backup to form, I would advise avoiding this road if possible. Hopefully they will clear out before the evening rush.
It seems like me posting about a traffic problem is usually enough to get it to clear up, who knows if it will work this time.
UPDATE 4:00pm: they have now stopped work and completely cleared out of the area.