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Hurricane Wilma (search) accelerated toward storm-weary Florida on Sunday and grew stronger, threatening residents with 110-mph winds, tornadoes and a surge of seawater that could flood the Keys and the state's southwest coast.

After crawling slowly through the Caribbean (search) for several days, Wilma pulled away from Mexico's Yucatan Peninsula as a Category 2 storm and, forecasters said, began picking up speed "like a rocket" as it headed toward the U.S. mainland. The storm was expected to make landfall around dawn Monday.

The southern half of the state was under a hurricane warning, and an estimated 160,000 residents were told to evacuate, although many in the low-lying Keys island chain decided to stay.

Click here to track Hurricane Wilma.

"I cannot emphasize enough to the folks that live in the Florida Keys: A hurricane is coming," Gov. Jeb Bush (search) said. "Perhaps people are saying, 'I'm going to hunker down.' They shouldn't do that. They should evacuate, and there's very little time left to do so."

At 8 p.m., Wilma's winds were just 1 mph shy of Category 3 status. As the storm crossed the Gulf of Mexico (search), forecasters said they saw no evidence of wind shear that they hoped would reduce the hurricane's intensity before it makes landfall in southwest Florida.

Wilma had battered the Mexican coastline with howling winds and torrential rains before moving back out to sea. At least three people were killed in Mexico, following the deaths of 13 in Jamaica and Haiti.

Forecasters expected flooding from a storm surge of up to 17 feet on Florida's southwest coast and 8 feet in the Keys. Tornadoes were possible in some areas through Monday.

Max Mayfield, director of the National Hurricane Center (search) in Miami, predicted Wilma would dramatically pick up speed as it approached Florida.

"It's really going to take off like a rocket," he said. "It's going to start moving like 20 mph."

Because the storm was expected to move so swiftly across Florida, residents of Atlantic coast cities such as Miami and Fort Lauderdale were likely to face hurricane-force winds nearly as strong as those on the Gulf Coast, forecasters said.

Wilma would mark Florida's eighth hurricane since August 2004 and the fourth evacuation of the Keys this year.

Fewer than 10 percent of the Keys' 78,000 residents evacuated, Monroe County Sheriff Richard Roth said.

"I'm disappointed, but I understand it," Roth said. "They're tired of leaving because of the limited damage they sustained during the last three hurricanes."

By Sunday evening, tornado warnings were already posted for parts of southwest Florida, and the hurricane's outer bands began lashing coastal areas in Wilma's path. A waterspout was spotted off Key West.

It was markedly different than conditions Sunday morning in the Keys, when sunshine beckoned boaters onto the water and many residents went about their normal routines.

"We were born and raised with storms, so we never leave," Ann Ferguson said from her front porch in Key West. "What happens, happens. If you believe in the Lord, you don't have no fear."

Some 100 Key West parishioners attended Mass at a Catholic church where a grotto built in the 1920s is said to provide protection from dangerous storms. Ray Price took his usual stroll down Duval Street to check out the ocean.

"Another day in paradise," Price said.

Some people shared that attitude on the mainland. At a park for recreational vehicles in Fort Myers Beach, Leonard Hasbrouck stood bare-chested as a fire truck rolled by blaring a warning.

"Mandatory evacuation," a firefighter shouted into a loudspeaker. "You are hereby ordered to leave your residence by the board of county commissioners of Lee County, Fla."

"They came by yesterday," Hasbrouck said. "I told them, 'I'm not going to ask you to rescue me."'

Tropical storm-force winds of at least 39 mph were expected to begin late Sunday, and the core of the hurricane was forecast to slice across the peninsula Monday, speeding northeast at up to 25 mph.

Gov. Bush wrote his brother, President Bush, asking that the state be granted a major disaster declaration for 14 counties ahead of the storm. Many of the areas bracing for Wilma were hit by some of the seven other hurricanes that either made landfall or brushed the state since August 2004.

The governor said state officials expected heavy rain and widespread power outages. The National Guard was on alert, and state and federal officials had trucks of ice and food ready to deploy.

The Federal Emergency Management Agency was poised to send in dozens of military helicopters and 13.2 million ready-to-eat meals if needed, spokesman Butch Kinerney said.

"We're ready for Wilma and, whatever the storm brings, we're set to go," Kinerney said.

George Delgado of Miami was still covering the windows of his house with plywood Sunday. He said he waited until the last minute to make sure the hours of work were necessary.

"I was hoping it would turn some other way," Delgado said.

At 8 p.m. EDT on Sunday, Wilma was centered about 170 miles west-southwest of Key West and moving northeast at about 15 mph. Hurricane-force wind of at least 74 mph extended up to 85 miles from the center and wind blowing at tropical storm-force reached outward up to 230 miles, the hurricane center said.

Weary forecasters also monitored Tropical Depression Alpha, which formed Saturday off the Dominican Republic and was briefly a tropical storm, the record 22nd named storm for the Atlantic season. It was the first time the hurricane center exhausted the regular list of names and had to turn to the Greek alphabet.

Alpha was not considered a threat to the United States.

On Florida's Gulf Coast, evacuation orders covered barrier islands and coastal areas in Collier and Lee counties, such as Fort Myers Beach, Marco Island, Sanibel and parts of Naples.

Visitors crossing the bridge into Marco Island Sunday were greeted by an electric sign that flashed, "EVACUATE, EVACUATE."

About 3,500 people were in shelters across the state, including roughly 850 people at the Germain Arena near Fort Myers, where evacuees pitched tents and placed mats on the ice rink where a minor-league hockey team plays. Cots and sleeping bags lined hallways outside the rink.

David Bright sat nearby on a chair, a Bible beside him. He's old enough to remember plenty of other hurricanes, including destructive Donna in 1960.

"I'm just doing a lot of praying that things will work out," he said. "I'm born and raised right here in Fort Myers, Fla., and just know you don't play with them."