Giant hurricane Dora grew in strength as it roared along Mexico's Pacific coast Thursday, but was expected to remain offshore, US and Mexican weather services said.
Dora nearly reached the top strength of five on the Saffir Simpson scale, the US National Hurricane Center said in its 1500 GMT bulletin.
The storm churned around 445 miles (715 kilometers) south-southeast of the luxury beach resorts of Cabo San Lucas on the Baja California peninsula, packing powerful winds of 155 miles (250 kilometers) per hour, the NHC said.
"Dora is expected to stay well offshore of Mexico" and to start weakening by Thursday night, it added.
Mexico's weather service warned of dangerous swells and high waves along four coastal states and said the storm was unlikely to touch the tourist resort areas on the tip of Baja California.
Mexican authorities also prepared for possible landslides in areas already hit by torrential rains that left five dead and affected 200,000 people last weekend.
The 2011 season's first named storm, Arlene, left at least 16 people dead in Mexico after it drenched much of the country and left hundreds of thousands homeless earlier this month.
Tropical storms and hurricanes in Mexico last year caused flooding and mudslides that killed 125 people, left hundreds of thousands homeless and more than $4 billion in damages.