Amtrak and its customers will share some of the hardship with New York City commuters during several weeks of disruptive repair work at Pennsylvania Station this summer, according to a revised schedule Amtrak officials have drawn up.

Among the changes Amtrak announced on Tuesday was the cancellation of three daily trains in each direction between Penn Station and Union Station in Washington.

In addition, four daily trains between Penn Station and Harrisburg, Pa., will start and end their runs in Philadelphia or Newark.

Amtrak’s popular high-speed Acela service between Washington and Boston will run its usual schedule during the disruption, which will start in early July and continue through the end of August. After a series of problems at Penn Station, including two derailments, Amtrak announced a few weeks ago that it had decided to accelerate repairs that would take tracks out of use for long stretches of time.

Those track closings will force significant changes to the schedules of the nation’s two busiest commuter train systems — the Long Island Rail Road and New Jersey Transit. The result, according to Gov. Andrew M. Cuomo of New York, will be a “summer of hell” for commuters.

The Long Island Rail Road, the biggest user of Penn Station, has not yet said how it will reduce its service to accommodate the repair work. New Jersey Transit has said that it will divert all of the trains on one of its lines — the Morris & Essex — from Penn Station to Hoboken Terminal, where riders will have to switch to the PATH train or ferry boats to get across the Hudson River.

New Jersey Transit said that there would be some changes to the schedules of its other rail lines and that it planned to publish those revised schedules in early June.

Amtrak’s chief executive, Charles Moorman, said the schedule cuts made by Amtrak, which owns and operates Penn Station, would be proportionally broader than those made by commuter lines.

“While Amtrak’s own service at Penn Station will face the largest impact of the three railroads in terms of proportional reductions in train service during the work period,” he said, “we will use all the tools we can, such as lengthening trains, to continue to provide capacity for our intercity travelers going to or from New York.”

The changes on the Harrisburg schedule involve shortening three daily round trips to start or end in Philadelphia, and a fourth to start and end at Newark’s Penn Station.

The Crescent, a train that travels between New York and New Orleans, will shorten its route to start or end in Washington during the disruption.

Amtrak officials have also discussed the possibility of rerouting some trains from Penn Station to Grand Central Terminal. Those trains run on Amtrak’s Empire line along the Hudson River and could make an eastward detour to run through the Bronx and Upper Manhattan.

Jim Fahey, director of the Association of Commuter Rail Employees, a 1,500-member union, said he had heard that three Amtrak trains would go in and out of Grand Central each weekday during the disruption. He said that rather than crossing the Spuyten Duyvil Bridge and running down the West Side of Manhattan to Penn Station, those trains would turn east and head toward Grand Central. He said the plan called for engineers from Metro-North Railroad to pilot the trains between Spuyten Duyvil and Grand Central, because Amtrak engineers are not familiar with the complex network of tracks at the terminal.

“Whoever came up with this idea to take some of the pressure off Penn Station, I give them kudos,” Mr. Fahey said. “Because it is a good idea.”

Christina Leeds, a spokeswoman for Amtrak, said no final decision had been reached on detouring to Grand Central.

Nancy Snyder, a spokeswoman for New Jersey Transit, said the agency was confident that Hoboken Terminal, which was damaged in a fatal train crash last fall, could handle the additional 23,000 passengers who ride Morris & Essex trains to and from Midtown Manhattan each day. Ms. Snyder pointed out that even more of New Jersey Transit’s Midtown Direct trains were diverted to Hoboken for several days after one of the recent derailments at Penn Station.

During that diversion, New York Waterway, which operates ferries on the Hudson, added a route between Hoboken Terminal and the ferry terminal at West 39th Street in Manhattan. The ferry company has offered to re-establish that route this summer; Ms. Snyder declined to comment on whether New Jersey Transit would support that idea.

Gov. Chris Christie of New Jersey said commuters who are diverted would receive steep discounts on their tickets and would not have to pay additional fares to transfer to a ferry or the PATH train.