KEY WEST, Fla. — With powerful Hurricane Ike on an uncertain course toward the Gulf of Mexico, many on these low-lying islands took a wait-and-see approach to evacuation orders today, perhaps a harbinger of the attitudes to come from Louisiana and Texas residents returning from an arduous evacuation and already showing signs of “hurricane fatigue.”

Forecasts show Ike crossing Cuba and skirting Key West by Tuesday on a trek to the warm waters of the Gulf of Mexico, slowly strengthening to perhaps Category 3 strength on its way to a landfall late in the week somewhere between the Florida Panhandle and the Texas coast.

And once again, New Orleans — still recovering from the weaker-than-expected Gustav — is squarely in the crosshairs.

In Key West, evacuation orders became mandatory Sunday for tourists and the approximately 25,000 residents alike, but traffic off the lone highway from the island was steady rather than jammed.

Mike Tilson, 24, was preparing to ride Ike out in his houseboat, only planning to evacuate if the storm takes a sudden turn to the north.

“I got tarps and champagne,” he said as he pushed a wheelbarrow of supplies including Heineken beer, ice and a loaf of bread down the dock.

“It’s just a good party. I’ll stay.”

At 5 p.m. EDT today, Ike was a Category 3 hurricane with sustained winds near 120 mph, located about 75 miles northeast of Guantanamo, Cuba, and moving west at 13 mph. It was forecast to track over Cuba, re-emerging over the island’s western coast Tuesday morning about 100 miles south of Key West as a Category 1.

Ike was a dangerous Category 4 hurricane packing 135-mph winds earlier, but the National Hurricane Center in Miami said it had weakened “a little” in recent hours.

President Bush declared a state of emergency for Florida because of Ike on Sunday and ordered federal money to supplement state and local response efforts.

Mayor Morgan McPherson of Key West said 15,000 tourists had already evacuated the region, and the Key West airport was set to close at 7 p.m. today.

Mr. McPherson warned that anyone who thinks staying through a major hurricane is “champagne time” hasn’t thought it through clearly. He said emergency vehicles would be pulled off the road if the area gets tropical storm force winds.

Still, many residents of the nation’s most southernmost city said they wanted to see what the storm does over Cuba and possibly reassess tomorrow.

Among them was the director of the Key West Art and Historical Society, Claudia Pennington, 61, who said she’s staying to care for the group’s three buildings and their contents. Don Guess, 50, was putting up plywood on a friend’s house today and said he was sticking around because the storm didn’t worry him.

At the Key West Convalescent Center, 70 sick and elderly residents were being evacuated by bus and ambulance to Sunrise on Sunday afternoon.

Edward Koen, 87, sat in his wheelchair outside the center today in the shade, staring up at the blue, sunny skies, waiting for the bus.

“Why should I be nervous, because of a hurricane?” Mr. Koen said. He’d rather stay put. “My gosh. I’ve been living here all my life.”

The reluctance to leave didn’t surprise the director of the Institute for Public Opinion Research at Florida International University, Hugh Gladwin, who has studied evacuations in Florida and after Hurricane Katrina.

“Yes, there’s always a certain number of people who won’t evacuate no matter what: they’re fatalistic — they like being in hurricanes,” Mr. Gladwin said.

Mr. Gladwin said he’s never seen more than 80% evacuation participation anywhere, even with the biggest and scariest hurricane bearing down. And it can be harder to get people to leave when they’ve evacuated recently.

That’s the case in New Orleans, where many of the 2 million people who fled the Lousiana coast ahead of Gustav had only just returned from arduous evacuation. In many cases, jammed highways turned routine trips to such evacuee havens as Birmingham and Memphis into 15-hour crawls.

Some New Orleans residents were already digging in their heels ahead of Ike.

David Myers, a 39-year-old physician who rode out Gustav with relatives in Baton Rouge before returning home to New Orleans on Tuesday, said it would take a Category 4 or 5 storm to chase him away again. He expects many other residents who ran from Gustav to balk at evacuating for Ike.

Governor Jindal of Louisiana said so-called “hurricane fatigue” should not prevent people there from leaving their homes for the second time in 10 days.

“We are likely going to have to become accustomed to evacuating more frequently than when we were younger,” he said.

Christopher Gargiule, 37, said evacuating for Gustav cost him and his wife, Joanne, more than $1,500, and that they can’t afford to leave again even if Ike forces another mandatory evacuation of the city. And they live in a house just 50 yards from a levee that had water splash over it during Gustav.

“We’re going to have to hunker down and cross our fingers,” Mr. Gargiule said.