Fiercest hurricane Wilma threatens Mexico, Florida

Hurricane Wilma became the fiercest Atlantic hurricane ever seen as it churned toward western Cuba and Mexico's Yucatan peninsula yesterday, and threatened densely populated Florida after having already killed 10 people in Haiti.

The season's record-tying 21st storm, fuelled by the warm waters of the northwest Caribbean Sea, intensified with unexpected and unprecedented speed into a Category 5 hurricane, the top rank on the five-step scale of hurricane intensity.

A US Air Force reconnaissance plane measured maximum sustained winds of 280 kph, with higher gusts, the US National Hurricane Centre said.

The plane also recorded a minimum pressure of 882 millibars, the lowest value ever observed in the Atlantic basin. The previous record was for Hurricane Gilbert at 888 millibars, which hit Mexico in 1988. That meant Wilma was stronger than any storm on record, including both Katrina, which devastated New Orleans in late August, and Rita, which hit the Texas-Louisiana coast last month.

"People need to be prepared. Get ready for this," said Police Chief Bill Mauldin of Key West, a vulnerable city at the tip of the low-lying Florida Keys island chain.

Authorities in the Keys told tourists to start leaving yesterday. The islands' 80,000 residents would be told to evacuate today, they said.

Storm warnings were in force for Honduras in Central America, where more than 1,000 people died this month after Hurricane Stan triggered mudslides that buried entire villages. Warnings were also in force for the Yucatan, Cuba, Belize and the Cayman Islands.

Wilma's rains have already killed up to 10 people in mudslides in deforested and impoverished Haiti, civil protection officials said.

The storm, which boasted an unusually tight eye of just 3.7 to 7.4 kilometres, was expected to bring rainfall of up to 64 centimetres to mountainous parts of Cuba, and up to 38 centimetres to Jamaica and the Cayman Islands, a wealthy British colony south of Cuba. Honduras and Mexico could expect up to 30 centimetres of rain, the hurricane centre said.

By 11 a.m. EDT (1500 GMT), the hurricane was about 520 kilometres southeast of Cozumel, Mexico.

Wilma was the 21st storm of the Atlantic hurricane season, tying a record set in 1933. It was also the 12th hurricane and tied the record for most hurricanes in a season set in 1969.

The season still has six weeks left to run but has already spawned three of the most intense hurricanes on record - Katrina, Rita and now Wilma. Hurricane experts say the Atlantic has swung back into a period of heightened storm activity that could last another 20 years. Climatologists also fear global warming could be making the storms more intense.

Wilma was moving west-northwest at 11 kph. A turn toward the northwest was expected in the next 24 hours. Once in the south-eastern Gulf of Mexico, Wilma was expected to make a sharp turn to the northeast, toward Florida.

The storm was not expected to threaten New Orleans or Mississippi, where Hurricane Katrina killed more than 1,200 people and caused more than $30 billion in insured damage.

It was also expected to miss oil and gas facilities in the Gulf of Mexico still reeling from Katrina and Rita.