Some Amtrak and Maryland commuter trains faced significant delays Tuesday evening and Wednesday morning after severe rainstorms knocked out signal power between Washington and Baltimore late Tuesday afternoon.

A fallen tree in Garrett Park, also related to the storms, delayed trains between Washington, Frederick County and West Virginia late Tuesday afternoon.

Some Maryland Area Regional Commuter (MARC) trains on the Penn Line were canceled Tuesday evening, and others were delayed up to two hours between Union Station and Baltimore due to speed restrictions of 15 mph.

The signal system functions much like traffic signals, using colored lights to tell train engineers when it is safe to proceed and at what speed, MARC officials said. During an outage of the signal system, trains are limited to 15 mph to allow engineers to stop safely if they see a problem, MARC officials said.

The Penn Line signal problems stretched into the Wednesday morning commute, causing more delays and some cancellations, MARC officials said.

A tree that fell across the tracks at Garrett Park along the Brunswick Line about 3:30 p.m. Tuesday caused delays to both MARC and Amtrak trains before it was removed by 5 p.m., MARC officials said.

Amtrak had 19 trains delayed between Baltimore and Washington on Tuesday evening because of the signal outage, said spokesman Marc Magliari. Those delays were between a half-hour and 2 1/2 hours, Magliari said.

The signal system was restored about 7:20 a.m. Wednesday, Magliari said, but delays rippled throughout the morning.