Gathering strength at a fierce pace, Hurricane Wilma grew into a Category 5 monster storm early Wednesday with 175 mph winds. Forecasters warned the storm was "extremely dangerous" and said a key reading of its pressure was the lowest ever recorded in the Atlantic basin.
"This will make this the most intense hurricane ever recorded in the Atlantic basin, stronger than Gilbert" in 1988, National Hurricane Center forecaster Jennifer Pralgo told CBS Radio News.
Wilma was dumping rain on Central America and Mexico, and forecasters warned of a "significant threat" to Florida by the weekend.
"We do expect Wilma to make landfall somewhere in the Florida peninsula, possibly on Saturday into Sunday, as a Category 3 hurricane," Pralgo said.
The storm gathered force rapidly over the last day. It was only Tuesday morning that Wilma grew from a tropical storm into a weak hurricane.
At 5 a.m. EDT, U.S. Air Force reconnaissance planes measured Wilma's top sustained winds at 175 mph, making it a Category 5 hurricane, the Hurricane Center said. At that time, the storm was centered about 170 miles south-southwest of Grand Cayman Island and about 365 miles southeast of Cozumel, Mexico. It was moving west-northwest at nearly 8 mph and was expected to turn northwest, the Hurricane Center said.
The Air Force plane recorded a preliminary pressure reading Wednesday morning of 884 millibars, the lowest minimum pressure ever recorded in a hurricane in the Atlantic basin. Lower pressure translates into higher wind speed.
Jamaica, Cuba, Nicaragua and Honduras were getting heavy rain from the storm, though it wasn't likely to make landfall in any of those countries. Forecasts showed it would likely turn toward the narrow Yucatan Channel between Cuba and Mexico's Cancun region — then move into the storm-weary Gulf.
With heavy rain, high winds, and rough seas already pounding coastal areas, flood-prone Honduras warned that Wilma posed "an imminent threat to life and property" and closed two seaports on its Caribbean coast. Neighboring Nicaragua also declared an alert. Authorities in the Cayman Islands had earlier called an alert.
Honduras and its neighbors already are recovering from flooding and mudslides caused earlier this month from storms related to Hurricane Stan. At least 796 people were killed, most of them in Guatemala, with many more still missing.
Cuba issued a hurricane watch for the western end of the island from Matanzas to Pioneer del Rio, as well as the Isle of Youth. Mexico issued a hurricane watch for nearly all of its Caribbean coast from Punta Gruesa to Cabo Catoche, an area that includes the resort of Cancun.
Wilma already had been blamed for one death in Jamaica as a tropical depression Sunday. It has flooded several low-lying communities and triggered mudslides that blocked roads and damaged several homes, said Barbara Carby, head of Jamaica's emergency management office. She said that some 250 people were in shelters throughout the island.
Although the storm was not expected to approach Florida until the weekend, some residents began buying water, canned food and other emergency supplies early. Many said they take every storm seriously now, after witnessing the devastation from a succession of hurricanes that have ravaged the southern United States.
"People have learned their lesson and know better how to prepare. We're not waiting until the last minute any more," said Andrea Yerger, 48, of Port Charlotte, Florida. She was buying material to protect her house, which had to be gutted because of extensive damage from Hurricane Charley last year.
So was the Days Inn in Punta Gorda, where Susan is the overnight desk clerk.
"We've been open about three weeks now. We were down for 14 months. Everything's brand new in here. They had to gut everything out after Hurricane Charley" last year, the woman, who asked that her last name not be used, told CBS Radio News.
Wilma's track could take it near Punta Gorda on Florida's southwestern Gulf Coast and other areas in the state hit by Hurricane Charley, a Category 4 storm, in August 2004.
"Kind of scary. I'm not ready for it," sighed Susan. "Sometimes it makes you wonder if you should just pack up and leave, and stay gone."
Forecasters urged Florida residents to closely monitor Wilma. The state has seen seven hurricanes hit or pass close by since August 2004, causing more than $20 billion in estimated damage and killing nearly 150 people.
In the Cayman Islands, authorities urged businesses to close early Tuesday to give employees time to prepare for the storm. Schools were ordered to close on Wednesday.
In Mexico, the MTV Latin America Video Music Awards ceremony, originally scheduled to be held Thursday at a seaside park south of Cancun, were moved up one day to avoid possible effects from Wilma.
Forecasters said Wilma should avoid the central U.S. Gulf coast devastated by Hurricanes Katrina and Rita earlier this year which killed more than 1,200 people and caused billions of dollars in damage.
"There's no scenario now that takes it toward Louisiana or Mississippi, but that could change," said Max Mayfield, director of the National Hurricane Center.
The storm is the record-tying 12th hurricane of the season, the same number reached in 1969. That is the most for one season since record-keeping began in 1851.
On Monday, Wilma became the Atlantic hurricane season's 21st named storm, tying the record set in 1933 and exhausting the list of names for this year.
The six-month hurricane season does not end until Nov. 30. Any new storms would be named with letters from the Greek alphabet, starting with Alpha.
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