Hurricane Darby moved further away from Mexican coasts on Friday and was expected to lose more speed over the weekend, the US National Hurricane Center said.
Darby grew into a Category 3 hurricane earlier on Friday. It had maximum sustained winds of 115 mph (185 kph) and was 265 miles (425 km) southwest of the Mexican beach resort of Acapulco.
The storm was moving west-northwest at 6 mph (9 kph).
"A turn toward the west or west-southwest with a decrease in forward speed is expected later tonight or early Saturday," the Miami-based hurricane center said.
Pacific hurricanes can damage tourist resorts along Mexico's coast but pose no threat to the country's oil industry, which is primarily located in the Gulf of Mexico.
Farther out in the Pacific, Hurricane Celia weakened to a Category 3 status. The system posed no threat to land as it roared across the Pacific and forecasters said it should dissipate by the middle of next week.
Celia, the first hurricane of the Pacific season, was 850 miles (1,370 km) southwest of the tip of Baja California and had maximum sustained winds of 120 mph (195 kph).
"Celia is forecast to weaken to a tropical storm by Sunday," the center said.
In the Caribbean, forecasters were monitoring a tropical depression that was could become the first storm of the 2010 Atlantic hurricane season on Saturday. A storm there could disrupt oil-siphoning efforts at BP's blown-out Gulf of Mexico well.
