Hurricane Jimena roared toward Mexico's Baja California as an extremely dangerous Category Five storm, Mexican officials said as they planned emergency evacuations for 20 000 families.

Jimena was packing winds of up to 155 miles per hour (250 kilometres per hour) but was expected to weaken slightly before making landfall in Baja California late on Tuesday or early on Wednesday, the National Weather Service said.

The centre of the hurricane was 285 miles (460 kilometres) south of Cabo San Lucas as of 0001 GMT on Tuesday, said the US National Hurricane Center (NHC), an American agency which tracks and predicts storms.

US forecasters put Jimena at a Category Four on the one-to-five Saffir-Simpson scale, but noted that the storm was "very near the threshold of Category Five status."

Residents of the northwestern peninsula frantically boarded up their homes and stockpiled goods as the most powerful hurricane of the year approached.

Jimena forced a major international conference on tax transparency to be moved from Los Cabos, a resort town on the southern tip of Baja California, and set up in Mexico City instead.

The Paris-based Organisation for Economic Co-operation and Development (OECD) said it had moved the event because of the "threat of severe damage posed by Hurricane Jimena."

Over 20 000 families at high risk

Baja California, a peninsula which spears south from the US state of California into the Pacific, was placed on high alert as emergency officials prepared contingency plans.

Francisco Cota, the head of the civil protection agency in Los Cabos, said any evacuation plan would focus on densely populated areas and valleys at greatest risk of flooding.

"It will place special emphasis on the more than 20 000 families who live in high-risk areas," he told journalists after a meeting of civil defence officials.

US meteorologists said Jimena could produce up to 15 inches (38 centimetres) of rainfall in isolated areas, and a total of five to 10 inches (13 to 25 cm) over the southern half of the Baja California peninsula and parts of western Mexico over the next few days.

The US State Department issued an alert to American citizens urging them to seriously reflect before risking travel to areas of Mexico and the United States lying in the storm's path.

"US citizens located in areas likely to be impacted by Hurricane Jimena and who do not have access to adequate and safe shelter should consider departing while commercial flights are still available," the warning said.

With gusty winds and rains already hitting La Paz, the capital of the peninsula's southern Baja California Sur state, residents were hastily boarding up windows and stocking up on groceries before the shops closed.

Jimena to make landfall as a major hurricane

"Jimena is moving toward the northwest near 10 miles per hour (16 kph)... and a turn toward the north-northwest with a gradual increase in forward speed is expected over the next day or so," the NHC said.

"On the forecast track Jimena will be approaching the southern portion of the Baja California peninsula on Tuesday."

The Miami-based agency said that although the strength of Jimena would fluctuate over the next day or so it was certain to make landfall as a major hurricane.

"A dangerous storm surge along with battering waves will produce significant coastal flooding along the Baja California peninsula. Preparations to protect life and property should be rushed to completion," the NHC warned.

Flooding and landslides have already been reported at the weekend in southern Mexican states as the hurricane churned its way up the Pacific coast.

Another storm, Kevin, far to the west of Jimena in the Pacific, had weakened considerably and no longer posed a threat, according to the NHC, which also warned Monday that a tropical depression may be developing east of the Lesser Antilles in the Caribbean Sea.

AFP

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