As volcanic ash shut down European airports for a fifth day, Marjan Inbar of NYC & Company, the city's tourism arm, said international tourists make up 20 percent of visitors to New York but account for half of all tourism spending.
Passengers at Kennedy International Airport said they were running low on money and vacation days, not to mention patience.
"We have been sleeping here for three days," Chantal Dierick, 56, of Tournai, Belgium, said near her airport cot. "One night in a hostel only to have a shower and a good bed. Now it's impossible because we have no money."
"Day by day we can see: Canceled, canceled. We don't know if the flight will be possible in one day, one week, two weeks," said Dierick, a school director, who was trying to get home after a vacation in Costa Rica.
Residents of the mini-encampments brushed their teeth and hair in restrooms; a consulate handed out apples, granola bars and chips. Some friendships were formed amid the mutual misery.
The Port Authority of New York and New Jersey, which runs the airport, planned to park trailers with shower stalls between two terminals on Monday afternoon.
Heiko Ung, 23, who was trying to get back home to Frankfurt, also spent the weekend at the airport, sleeping on a green cot with a white blanket provided by the American Red Cross. He said his airline told him he might fly out Wednesday.
"After six days of shopping in New York we need a hotel for free. I still get paid but not forever. That hurts," he said. "I have 26 days for a year and now it's going away."
Overall, NYC & Co. estimates the city could lose $250 million in tourism-related revenue because of the ash cloud.
For every 1,000 visitors who do not arrive, the city loses approximately $1.5 million, it said.
In a worst-case scenario, NYC & Co. estimates that 160,000 visitors could cancel their trips to New York over a two-week period, beginning last Thursday. In a typical April, 12,000 people from Europe visit New York City and spend $3 million a day.
But the agency said it assumes that 80 percent of those visitors will come to the city at some point later this year, so there's a significant chance that the loss could be made up, said NYC & Co. spokeswoman Tiffany Townsend.
"We will actively work to continue to attract visitors to the city for both business and leisure travel," she said.
Mayor Michael Bloomberg announced Friday that the city tourism agency had helped arrange 15 percent discounts at 30 hotels over the weekend for those unable to receive hotel vouchers from their airlines. The city's official tourist Web site, www.nycgo.com, was offering discounts on Broadway tickets, other events and restaurants.
Some events were affected by the flight disruptions.
Organizers of the Tribeca Film Festival say some directors and actors may not make it to New York. The festival starts Wednesday.
Mandy Rowse, 47, who was trying to get home to London where she works in a plumbing shop, said she had planned to fly to Heathrow in Sunday.
"I'm making the best of it. The hotels are fully booked," said Rowse, who is traveling with several friends. "We phoned home and they are trying to find us a hotel. If we stay here, we won't be spending any money."
She said the airline said they would be able to go home April 30 and gave them a spending allowance. They planned to stay in the airport.
By Associated Press Writer Megan K. Scott; AP Writer Ula Ilnytzky contributed to this report