Hurricane Wilma (search) sent ocean waves surging over the narrow strip of land that holds Cancun's resort hotels Saturday, flooding streets several yards deep as some 30,000 tourists huddled in hotels and shelters taking on water.

The slow advance of the storm, which earlier killed 13 people in Haiti (search) and Jamaica, gave Florida more time to prepare but meant another day of misery for people riding out shrieking winds in hot, leaky shelters with little food and water.

The storm weakened Saturday to a Category 2 with sustained winds near 110 mph, down 25 mph from overnight, according to the National Hurricane Center (search) in Miami.

Click here to track Hurricane Wilma.

With the storm crawling across the tip of the Yucatan Peninsula, emergency crews were trapped inside and it was impossible to gauge the extent of damage. City and hospital officials had no immediate reports of deaths.

During the brief lull as the eye of the storm passed over Cancun (search), dozens of people were seen looting at least four convenience stores, carrying off bags of pasta, soda and canned tuna. Others dragged chairs, tables and lamps from a furniture store. Police guarded only larger stores, including a downtown Wal-Mart and appliance store.

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 (search) 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 crept toward this city.

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.

A hurricane watch and mandatory evacuation order were issued Saturday for the Florida Keys. Many people in the low-lying island chain and parts of the mainland began leaving Friday.

"Florida should take advantage of the slow pace and use this time to stock up on supplies and prepare," Gov. Jeb Bush told reporters. Wilma would be the eighth hurricane to hit or pass near the state since August 2004.

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.

On Cozumel, a popular cruise ship destination 11 miles offshore, Jorge Ham, 26, a fruit and vegetable salesman, said winds had dropped significantly. He told The Associated Press by phone that he didn't see catastrophic damage during a brief tour of downtown.

"There are broken windows, downed trees, fallen power lines, but nothing else," he said. "People have taken shelter."

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.

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."

Information about damages was limited because of downed communications and officials did not expect to get to Cozumel until late Saturday at the earliest to assess the situation.

At 2 p.m., the hurricane's eye was just west of Cancun and about 400 miles southwest of Key West.

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."

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 had to be ferried to hospitals.

The storm 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.

Meanwhile, a tropical depression formed Saturday south of Puerto Rico, prompting a tropical storm warning for Haiti and the Dominican Republic. It could strengthen into Tropical Storm Alpha later in the day. Letters from the Greek alphabet would be used because Wilma was the last name on the list this year. That has never happened in roughly 60 years of regularly named storms.