Metro is trying various ways to make the parking pinch easier for riders in the short term and find solutions for the long term besides building new lots. The transit agency has been testing sensors at its Fort Totten station to show drivers which spots are open from afar. Now it plans to expand the system to Rockville by the end of the year, Metro Parking Director Patrick Schmitt said.

Next month, he said, the transit agency also hopes to have signs at a surface lot at the Vienna station showing when the lot is full so riders don’t enter if the spots are already gone.