For updates Sunday on the status of specific trains, SEPTA urged riders to check its website ( www.septa.org), call its customer-service line (215-580-7800), or follow traffic reports on local news.
The strike, the first in 31 years, was short-lived. Striking SEPTA railroad workers had erected pickets early Saturday, surprising travelers who found themselves without train service.
Gov. Corbett had asked Obama to appoint a presidential emergency board to mediate the labor dispute and compel the striking rail engineers and electrical workers to return to work for 240 days.
SEPTA officials had said a return would take at least 12 hours after an order from the president, because equipment needed to be inspected and crews assembled.
The veteran arbitrators appointed to the board are Richard R. Kasher, Ann S. Kenis, and Bonnie S. Weinstock. The board will meet with both sides and within 30 days deliver a report to Obama recommending how the dispute should be resolved. But that is likely to be only a temporary solution, as officials are already predicting another strike in February.
Regional Rail trains carry about 60,000 riders on 126,000 trips on a typical weekday, about 15 percent of SEPTA's total ridership.
"I have requested federal intervention from the President to immediately mediate the ongoing dispute between SEPTA and the engineers and electricians unions," Corbett said in a statement Saturday. "It is imperative that parties continue to work toward an agreement for the benefit of the tens of thousands of people who use SEPTA rail every day."
"The people of Philadelphia and the surrounding region expect and deserve a safe and efficient rail system to get them to work, medical appointments, school, and recreation," the governor said. "I call on both parties to work together, find common ground and place the riders at the forefront of mind in their discussions."
Corbett's letter to Obama had requested that the executive order "be made effective immediately" to "prevent any further disruption to commuter rail service and the unnecessary inconvenience to the riding public in the southeastern Pennsylvania region."
Neither side in the labor dispute was overjoyed by what they saw as a temporary solution to a years-long battle. Management and labor both said they thought another strike is likely in February, when the 240-day period expires.
"That's the worst possible time for a strike," Bruno said, "with everybody in school and 72 inches of snow on the ground."
"We're happy for our riders," SEPTA spokeswoman Williams said. "No one wants our riders to be inconvenienced by a service interruption."
The last SEPTA Regional Rail strike was in 1983, and that one lasted 108 days.
Earlier Saturday, striking engineers had posted pickets at all locations where they typically report to work, including rail yards and some stations.
A handful of train engineers sat in lawn chairs and held signs outside the Lansdale station. They said they could not comment on the strike. SEPTA transit police said the day had been calm.
The pickets left after learning of the governor's action.
Inside the station, a ticket agent said he had turned away about 15 people looking to buy tickets by noon Saturday.
"I hope the train strike gets settled - and that it doesn't last as long as the last one," said Mitchell Cooper of Lansdale, sitting on a bench outside the station. "But as I am a working man, I can empathize with the people on strike."
In Norristown, a handful of travelers waited on the platform for a train that would never come.
Abram Gathers, 24, of Norristown, was dressed to the nines and on his way to a wedding in Philadelphia.
"I think it's ridiculous - and bad timing," he said, surprised by the strike. "It's summer, events are starting to happen, and people need to get into the city." He said he would take a bus.
Foot traffic was light at the Market East station, where signs on the outside doors warned of the service suspension. Inside, doors to the train platforms were closed, trash cans blocking the escalator.
But there, too, an attendant at the information desk saw a steady trickle of confused and frustrated passengers.
"No one told me anything," said Solomon Byrd, 21, who works at Philadelphia International Airport.
Byrd, who lives in Deptford, normally drives to a PATCO station, gets off at Eighth and Market, and walks to catch the Airport Line train at Market East.
Not Saturday. After a call to his boss, Byrd decided to take a taxi to work, for which he would get reimbursed. That would work for the moment, to get to work. "How about getting home?" he wondered.
Spokeswoman Williams had said SEPTA officials were "shocked and flabbergasted" that the railroad workers went on strike.
"Now, they are not only not going to get their 11.5 percent raises, but they are not going to get paid and not going to get their health benefits," she said before Obama signed the executive order.
The 220 engineers and 210 electrical workers had announced their plans to strike after SEPTA's decision to impose management's terms to settle the long-running labor dispute.
SEPTA had alerted union officials Monday that it would implement previously offered pay raises, effective Sunday.
The raises were based on the pattern established by the contract settlement in 2009 with SEPTA bus drivers and subway operators represented by Transport Workers Union Local 234.
Those increases would have given electrical workers a raise of 11.5 percent Sunday, and the engineers would have gotten a 5 percent raise Sunday and an additional 3.5 percent raise July 6, SEPTA said.
Wages for electrical workers would have increased by about $3 to $29.50 an hour, on average. Electrical workers on average earn $55,120 a year, not counting overtime. The top wage rate for engineers would have increased by $2.64 per hour, to about $32.50 an hour. Engineers, who typically work six-day weeks, now earn an average of $95,290 a year, SEPTA said.
The railroad workers have two major objections to the SEPTA offer: They want the raises to be retroactive to the expiration of their last contracts, and they want an additional 3 percent raise, which they say represents the value of a pension benefit increase received by the TWU in 2009. The railroad workers are in a different pension plan from the TWU.
SEPTA general manager Joseph Casey said the pension benefit increase of $4 million a year for the TWU is offset by a higher contribution now paid by the workers. SEPTA maintains there is no cash value from the pension benefit increase.
Ben Cieply, who is completing a postdoctorate in microbiology at the University of Pennsylvania, climbed the steps to the high-speed platform Saturday morning. A Pittsburgh native currently living in Horsham, he said public transportation options were better here than in his hometown - but now he's come to rely on Regional Rail to get to work.
On Saturday, Cieply was trying out a new route to campus: a 25-minute drive to Norristown, then a ride to 69th Street on the high-speed line, then a trolley ride to 30th Street. The route would add half an hour to his commute, he estimated.
"I know they're looking out for their own well-being," he said, referring to the SEPTA workers. "But the people they'll really hurt are regular commuters."
But now, until February at least, commuters shouldn't have to worry.