Hurricane Hilary strengthened into a major storm in the Pacific on Friday and was expected to further intensify before approaching Mexico's Baja California peninsula over the weekend, forecasters said.
Heavy rainfall was also expected in the southwestern United States as the storm moves north, the US National Hurricane Center (NHC) said.
Hilary was packing maximum sustained winds of about 140 miles (225 kilometers) an hour, according to the NHC.
That made it a major Category Four hurricane -- the second-most powerful on the Saffir-Simpson scale of one to five.
Hilary was located about 425 miles south of the tourist resort of Cabo San Lucas on the southern tip of Baja California, the NHC said.
"Rapid intensification is expected to continue through this morning," it predicted.
"Hilary is expected to produce rainfall amounts of 3 to 6 inches, with isolated maximum amounts up to 10 inches, across portions of the Baja California Peninsula through Sunday night. Flash flooding, locally significant, will be possible," it added.
The storm brought rain and rough seas to areas along Mexico's southwestern Pacific coast, including the tourist resort of Acapulco.
In the United States, parts of southern California and southern Nevada could see heavy rain through early next week, the NHC said.
Hurricanes hit Mexico every year on both its Pacific and Atlantic coasts, usually between May and November.
