From coast to coast, transit agencies are planning for layoffs and pared-down service as the coronavirus pandemic decimates budgets and a federal stimulus package remains stalled in Congress.

In New York, the nation’s largest transit system is preparing to cut subway service by 40 percent while it considers a nearly $3 billion loan from the Federal Reserve. Boston is proposing to eliminate ferry service and shorten hours of operation on its rail system.

And in the nation’s capital, Metro on Monday announced plans to eliminate weekend rail service to bridge a nearly $500 million gap in next year’s operating budget — equivalent to one-quarter of what the transit agency typically spends annually to run the system.

The stark vision of the Washington region operating without weekend Metro service for the first time in decades jolted residents, as well as lawmakers who have spent months debating the need and scope of a possible second coronavirus relief package.

“It would be stupidity on steroids if Congress left for Christmas without doing an interim package as a bridge,” said Sen. Mark R. Warner (D-Va.), citing Metro’s plight while he pushed for a breakthrough during stimulus discussions.

Transit agencies have been warning for months about enormous deficits, but as they begin announcing proposed cuts, transit leaders say, people are realizing how intertwined public transportation is with their local economies and lives.

In New York, where the rate of ridership losses during the pandemic has far exceeded what the system lost during the Great Depression, the Metropolitan Transportation Authority is proposing cutting 40 to 50 percent of service on the subway, bus and commuter rail, and laying off more than 9,300 workers.

The effects would reverberate outside the transit system and result in about 450,000 regional job losses and a $65 billion cut to the region’s gross domestic product, according to a New York University study.

“This is a once-in-100-years fiscal tsunami that the MTA and our counterpart transit agencies across the country, including in Washington, D.C., are facing,” MTA chief executive Patrick J. Foye said. “This is not a negotiating tactic. It’s not a stunt. It is kind of grim reality.”

In San Francisco, where the Bay Area Rapid Transit System faces a $200 million shortfall through July 2022, the agency has unveiled an incentive program for retirement-eligible employees in hopes of avoiding layoffs among its 4,200-member workforce.

The system was among the first in the country to announce service cuts and a hiring freeze in hopes of conserving cash. At the end of March, it reduced operating hours — closing at 9 p.m. instead of midnight on weekdays and opening at 8 a.m. instead of 6 a.m. on Saturdays.

At the beginning of April, it reduced train service on some lines. The agency recently began adding back some services in hopes of luring riders, but funding concerns are dire.

“We’re in a fight for our life,” BART spokeswoman Alicia Trost said.

The Chicago Transit Authority is facing sharp ridership declines and a $375 million deficit. But instead of cuts, it has moved forward with normal operations, expecting the federal government to come through with aid.

Last month, its transit board approved a $1.6 billion operating budget that avoids changes to service and fares.

Metro, the nation’s third-largest transit system, is proposing to cut weekend rail service, close 19 of 91 stations, shorten hours of operation, slash bus routes by more than half and lay off 2,400 workers starting in July to meet a $494.5 million deficit in the fiscal year. The layoffs are in addition to 1,400 positions it hopes to eliminate through buyouts because of a $176.5 million shortfall this fiscal year.

Metro operates in a region where nearly 10 percent of households don’t have cars, including nearly 36 percent of those in D.C., according to census estimates. Several residents voiced opposition Monday to Metro’s proposals.

“I work multiple jobs to support myself, but cuts to Metrorail and Metrobus mean no work,” said Matty Shafran, 23, who lives in Bethesda and works as a tutor in Rockville and Silver Spring. “If Metrorail were to cut weekend services and Maryland bus routes as they are proposing, I would be unable to find alternative routes to my weekday and weekend jobs without spending $60 to $100 a week on Uber, for which I do not have the budget.”

Tysons Partnership, an alliance of banks, businesses, restaurants and developers in Northern Virginia’s heavyweight commercial district of Tysons Corner, said Metro’s proposal would be crushing.

Chief executive Sol Glasner said the proposed cuts “would cause profound economic harm to Tysons and the region’s other urban centers, all of which are dependent on transit.”

D.C. Del. Eleanor Holmes Norton (D), the District’s nonvoting congressional representative who also chairs the House Transportation and Infrastructure subcommittee on highways and transit, said eliminating weekend and late-evening rail service would also damage the city’s restaurant and tourism industry.

“Everywhere you look, we’re hit in the gut by these cuts,” she said.

Alexandria Mayor Justin Wilson (D) said Metro’s footprint is closely tied to the region’s growth and redevelopment.

“We have hundreds of millions of dollars of land use just in Alexandria, and billions across the region, that is happening because of proximity to a functioning transit system,” he said.

Transit systems say it’s not too late to roll back planned cuts if the federal government can send them checks. Some, like Metro, could stop layoffs and bring service back to current levels, but others, such as Boston’s MBTA, may move forward with proposed cuts and downsize service with the reduced demand until ridership begins to grow.

Several stimulus proposals were circulating Tuesday on Capitol Hill, including a $908 billion plan offered by a bipartisan group of senators. That proposal would allocate $45 billion for transportation with about $15 billion for mass transit systems. But aides were quick to note that details remain fluid.

Paul P. Skoutelas, president of the American Public Transportation Association, called the inclusion of transit a positive sign, but said transit systems need at least double that for stability.

“These agencies have no place to go,” he said. “And, quite frankly, state and local governments are not in a position to be able to backstop them or to provide any funding relief.”

Sen. Tim Kaine (D-Va.) said he hoped for more transit funding, but without an agreement from Republicans in the GOP-led Senate, making additional demands “would just be like something I put on my Christmas list that Santa didn’t bring.”

He said he worried that without relief in the near term, a depressed public transit system will make it harder to boost the economy because so many workers rely on it.

“We’ve got to get a deal. So I am encouraged by the bipartisan framework. I’m encouraged they recognized public transit is a key priority,” Kaine said.

Sens. Chris Van Hollen and Ben Cardin, both Democrats from Maryland, said they also support relief for public transit in any relief package.

But the $908 billion package received a cool reception Tuesday from the White House, where press secretary Kayleigh McEnany said it “has not been a topic of discussion.”

Senate Republicans offered their own plan that included more assistance for small businesses but no additional funding for state and local governments or help for public transit agencies.

Senate Majority Leader Mitch McConnell also said senior Republicans received a separate coronavirus relief proposal Monday night from House Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles E. Schumer (D-N.Y.). However, Democratic aides declined to discuss what it contained.

House members expressed a mix of frustration and urgency on Tuesday, noting the lack of any Senate consensus.

“The House passed two major pieces of legislation that would provide [Metro] with desperately needed funding to avoid these drastic measures, yet the Senate has refused to act,” House Majority Leader Steny H. Hoyer (D-Md.) said in a statement.

Rep. Don Beyer (D-Va.), who represents Alexandria and Arlington, said that without relief, Metro will find itself in an “apocalyptic” situation.

Rep. Gerald E. Connolly (D-Va.), chairman of the House subcommittee on government operations and a longtime Metro advocate, said, “If we want to guarantee transit systems are here in the future, the federal government must immediately provide financial support.”

Virginia Gov. Ralph Northam (D) said Metro’s proposed cuts were “nothing short of devastating,” while Maryland Gov. Larry Hogan (R) said it was “yet another reason Congress needs to step up.”

City and county leaders expressed concern for their communities but also for Metro workers, who are facing the possibility of layoffs before the holidays.

Prince George’s County Executive Angela D. Alsobrooks (D) said the proposed cuts are “deeply concerning” because as many as 2,100 employees whose positions might be cut live in the county.

“They are the essential workers who have literally kept the region moving, and their livelihoods are at stake,” she said. “This is when people need their health care and their jobs.”

Others noted that public transit will soon gain a supporter in the White House.

A frequent Amtrak rider between his home in Delaware and D.C., President-elect Joe Biden has prioritized transit in his broad $2 trillion “Build Back Better” infrastructure and energy plan.

Said Libby Garvey (D), chairwoman of the Arlington County Board: “January 20 can’t come soon enough.”

Rebecca Tan, Ovetta Wiggins, Antonio Olivo, Jeff Stein, Patricia Sullivan, Rachel Chason and Gregory S. Schneider contributed to this report.