Hurricane Rick continued to weaken in the Pacific off the coast of Mexico and was downgraded further to a tropical storm Monday evening as it approached the southern tip of Baja California.

As of 8 p.m. PT on Monday, Rick's maximum sustained winds had died down to about 113 km/h, according to the U.S. National Hurricane Center in Miami, Fla.

Rick was a Category 5 storm on Saturday but its power steadily decreased, according to the centre. A Category 5 hurricane is the highest on the Saffir-Simpson scale and is reached when winds exceed 249 km/h.

The hurricane is centred about 465 kilometres south-southwest of Cabo San Lucas, Mexico, and is moving northwest at about 13 km/h.

The Mexican government changed the hurricane watch to a tropical storm watch for the southern Baja California peninsula in Mexico from Agua Blanca southward on the west coast and from La Paz southward on the east coast, including Cabo San Lucas.

Rainfall is spreading across parts of southern Baja California and northwestern Mexico, and may produce life-threatening flash floods and mudslides, the centre said.

Large swells will continue to affect parts of the southern Baja California coast over the next couple of days, causing potentially dangerous surf conditions, the centre said.

With files from The Associated Press