MIAMI, Oct 18- Hurricane Rick strengthened further late Saturday, becoming what forecaster described as the second-strongest storm on record to hit the eastern north Pacific Ocean.
Rick reached top Category 5 status on Saturday as it barreled up Mexico’s Pacific coast with winds roiling at 180 miles (285 kilometers) per hour, US forecasters said.
The storm roared to the top of the Saffir-Simpson scale after warm waters prompted Rick’s precipitous rise from a Category 1 to a Category 5 system in less than 36 hours.
"With 180 mph winds, Rick becomes the second-strongest eastern north Pacific hurricane on record after Linda of 1997," the US National Hurricane Center (NHC) said.
At 0300 GMT Sunday, Rick was around 605 miles (975 km) south-southeast of the resort town of Cabo San Lucas as it headed west-northwest at 14 miles (22 km) per hour, parallel to Mexico’s southern coast, the US National Hurricane Center (NHC) said.
It was also 295 miles (475 km) south southwest of Manzanillo, one of the largest ports in the Americas.
The "extremely dangerous" storm, the Miami-based monitoring center said, was expected to remain offshore of Mexico’s southern coast over the weekend.
Rick was expected to pass near Mexico’s southern Baja California peninsula on Wednesday and make landfall in northwestern Mexico on Thursday.
US forecasters said residents in nearby areas should monitor the hurricane’s progress.
Outer rainbands associated with the storm would continue to affect Mexico’s southern coast through the night, the NHC said, along with "potentially dangerous surf conditions" caused by large swells.
The seventh hurricane of the eastern north Pacific 2009 season, Rick comes on the heels of Tropical Storm Patricia, which last week placed Los Cabos on Baja’s southern tip under a state of emergency, before petering out.
The peninsula was battered in early September by Hurricane Jimena, which ripped roofs off houses and caused floods that killed at least one person.