With the storm crawling across the tip of the Yucatan Peninsula, emergency crews were trapped inside by 115 mph winds and it was impossible to gauge the extent of damage. City and hospital officials had no immediate reports of deaths.
The storm shattered windows and tore off hotel roofs, turning hallways into wind tunnels and sending rain into rooms. Furniture pushed up against windows in improvised barriers was blasted aside by howling winds.
At least one shelter in downtown Cancun had to evacuate 1,000 people overnight because the ceiling threatened to collapse. Office furniture and other debris bobbed in the waters sloshing between buildings where some people watched from upstairs balconies.
After battering Cozumel Island with 140 mph winds Friday, Wilma came ashore overnight near Playa de Carmen in a sparsely populated area of luxury resorts about 30 miles south of Cancun and creeped toward this city, weakening to a Category 3 storm.
The storm was expected to pummel the tip of Yucatan all day Saturday before moving into the Gulf of Mexico, curling around Cuba's western end and sprinting toward Florida for an expected landfall Monday.
In Florida, residents began leaving the Keys and parts of the mainland Friday. Scattered gasoline shortages were reported and traffic jams backed up highways as people fled Florida's west coast.
Winds caused severe damage in Playa de Carmen, flattening dozens of wood-and-tarpaper houses and tossing rooftop water tanks and wooden window coverings through the air. Communications were cut off with Cozumel, a popular cruise ship destination 11 miles offshore.
Damage was intensified by the storm being nearly stalled atop Yucatan since Friday.
"This is the equivalent of having four or five hurricanes of this size pass over one after the other, given the amount of time we have been suffering hurricane-force winds," said Quintana Roo Gov. Felix Gonzalez Cantu, whose state includes Cancun. "Never in the history of Quintana Roo have we had storm like this."
Sea water flowed through Cancun's evacuated beachfront hotel zone, which lies between the ocean and a lagoon. Shop windows broke, falling trees crushed cars and pay phones jutted from waist-deep water.
At the Xbalamque Hotel in downtown Cancun, tourists and local residents listened in horror as windows shattered, the wind howled and the building shook.
"I never in my life wanted to live through something like this," said Guadalupe Santiago, a 27-year-old cook. "There are no words" to describe it."
Jan Hanshast, a tourist from Castle Rock, Colo., stood in the flooded hallway.
"My son's starting to lose it. He's tired and hungry," he said. As another howling burst of wind buffeted the building, he added, "Hearing things like that doesn't help."
Outside the shelter, the air was filled with debris, including pieces of buildings that were beginning to crumble under the constant lashing.
The U.S. National Hurricane Center in Miami said the storm was "really clobbering" the areas around Cozumel and Cancun.
"It's going to be a long couple of days here for the Yucatan Peninsula," said Max Mayfield, the center's director.
Gonzalez Cantu called the destruction "tremendous," but information was limited because of downed communications. Officials did not expect to get to Cozumel until late Saturday at the earliest to assess damage.
At 11 a.m. EDT, the hurricane's eye was just outside Cancun and about 400 miles southwest of Key West, Fla. Hurricane force winds extended out 85 miles from the eye and gale force winds up to 200 miles.
Juan Luis Flores, an emergency services official in Quintana Roo state, said about 65,000 people had been evacuated before the hurricane hit Mexico. Civil defense chief Carmen Segura assured people "their families are protected as they should be."
Many tourists found themselves sleeping on the floors of hotel ballrooms, schools and gymnasiums reeking of sweat because there was no power or air conditioning. Power was cut to most of the region before the storm as a precaution.
Scott and Jamie Stout of Willisville, Ill., were spending their honeymoon on a Cancun basketball court with a leaky roof.
"After one more day of this, I believe people will start getting cranky," said Scott Stout, 26. "Things could get messy."
The Stouts, at least, had food and coffee. Devon Anderson, 21, of Sacramento, Calif., was sharing 10 rooms at a rundown Cozumel school with 200 other Americans.
"We are all sleeping on the floor," Anderson said. "There's no food, no water."
Hotels being used as shelters pushed furniture up against windows, but the wind blasted through the improvised barriers. Water poured into rooms and hallways through broken windows. People at some shelters slept under plastic sheeting.
Mexican officials said about 20,000 tourists were at shelters and hotels on the mainland south of Cancun and an estimated 10,000-12,000 were in Cancun itself. About 50 hotels there were evacuated.
Cancun Red Cross director Ricardo Portugal said the biggest problem so far were "nervous crises," and 11 pregnant women who had gone into early labor and had to be ferried to hospitals.
As the storm lashed Yucatan, it also pounded the western tip of Cuba, where the government evacuated more than 500,000 people. Forecasters said Wilma could bring more than three feet of rain in parts of Cuba.
Waves of up to 21 feet crashed on the westernmost tip of Cuba and heavy rains cut off several small communities. About 7,000 residents were evacuated from the coastal fishing village of La Coloma in Cuba's southern Pinar del Rio province.
Early Wednesday, Wilma briefly became the most intense hurricane recorded in the Atlantic with 882 millibars of pressure, breaking the record low of 888 set by Hurricane Gilbert in 1988. Lower pressure brings faster winds.