Tropical Storm Lorena swirled off Mexico's Pacific coast Friday, dumping heavy rain and prompting authorities to prepare shelters for the evacuation of 30,000 people from the resort of Los Cabos.

The storm was 50 kilometers (31 miles) southeast from the tip of Baja California state at 1800GMT, with maximum sustained winds of 65 kilometers per hour (40 miles per hour), according to the National Weather Service.

The storm's center could skirt the peninsula's coast late Friday and make landfall as a weaker tropical depression on Saturday, the service said.

Authorities decided to prepare 18 shelters in Los Cabos due to the intense rainfall, said the municipal civil protection director, Wenceslao Petit.

He told AFP that officials expect to "evacuate some 30,000 people from the high risk areas of this municipality. They won't all go to shelters. Some will stay with relatives."

The hotels in the beach resort of Cabo San Lucas, which is part of the Los Cabos municipality, have their own shelters for tourists.

Another 3,500 people will be evacuated from the town of La Paz in the state of Baja California, which is on the northern half of the peninsula.

The US National Hurricane Center said Lorena could produce three of six inches of rainfall and bring potentially life-threatening floods and mud slides.

Meanwhile, another storm, Gabrielle, has lost much of its punch and now is being classified as a tropical depression, after lashing Puerto Rico and other parts of the Caribbean Thursday with torrential rains.