Hurricane Jova was strengthening as it headed for the southwestern Mexican coast, US meteorologists said Sunday, warning the system would likely grow further in the coming days.
The category one hurricane was at 0900 GMT packing maximum sustained winds of up to 85 miles per hour (140 kilometers per hour), said the Miami-based National Hurricane Center.
Mexican authorities warned of landslides from heavy rain generated by the hurricane of the season, affecting five coastal states along the west coast.
The storm was veering eastward towards the Mexican Pacific coastline, where it could make landfall by Tuesday, meteorologists said.
Jova was expected to strengthen in the coming days as it moved eastward. In its latest advisory, the NHC said the system was some 385 miles (615 km) west-southwest of the Mexican coastal city of Manzanillo.
Tropical storm Irwin, also in the eastern Pacific, meanwhile continued to weaken after losing hurricane status late this week, as it roiled the sea around 865 miles (1395 km) southwest of the southern tip of Baja California.
The NHC said Irwin, which posed no threat to land, was expected to weaken further in the coming 24 hours, with current maximum winds around 45 mph (75 kmh).
Way out in the mid-Atlantic basin, the hurricane center said post-tropical cyclone Philippe was moving steadily to the northeast, and similarly posed no threat to land.
Philippe had on Thursday become the fifth hurricane of the 2011 Atlantic season but was too far away to have any impact on coastal areas.
It had been the 16th named storm of the season, which has seen four other hurricanes so far, including Irene, a massive system that unleashed deadly floods and storm surges in the eastern United States.
The Atlantic hurricane season ends on November 30, according to the NHC.