Updated

Hurricane Ivo weakened slightly early Friday and was expected to become a tropical storm over the weekend before plowing into southern Baja California.

The Category-1 storm had sustained winds of about 75 mph and was moving to the north at about 8 mph.

It was expected to hit a relatively desolate stretch of coastline on Mexico's Baja California peninsula early Monday, although forecasters warned that the storm's path was unpredictable because of a high pressure system further north off the coast of California.

"There's a lot of uncertainty with the track," said Eric Christensen, a meteorologist at the U.S. National Hurricane Center in Miami.

Authorities in the resort of Cabo San Lucas began advising residents to buy water and food. Emergency officers planned to meet Friday to assess Ivo's progression.

The area was hit Sept. 4 by Hurricane Henriette, which killed 10 people, including two Japanese tourists, and destroyed about 2,000 homes.