Puerto Vallarta, Mexico - Hurricane Jova bore down on Mexico's Pacific coast on Tuesday, threatening to hit one of the country's busiest cargo ports and tourist resorts with destructive waves, heavy rainfall and flooding.

In the popular resort town of Puerto Vallarta, it was not yet raining on Tuesday morning but people were bracing for the biggest storm in nine years by boarding up shops and staying at home.

The Category 3 storm, with top winds reaching 115 miles per hour (185 kph), was about 120 miles (190 km) southwest of the port city of Manzanillo at 11 a.m. EDT (1500 GMT), the U.S. National Hurricane Center said.

The Miami-based hurricane center said Jova would slam into the Mexican coast later on Tuesday afternoon or evening, to the northwest of Manzanillo on a stretch of coast dotted with beaches south of Puerto Vallarta.

"People think it's not going to do anything, but it's moving slowly and it's going to be dangerous," said bank worker Jose Avila, who was watching the waves from Puerto Vallarta's boardwalk. "They thought that last time and it destroyed everything."

Puerto Vallarta's last big hurricane was Kenna in 2002, which hit with winds of up to 144 mph (230 kph) and flooded streets close to the shore, causing damage that took authorities days to clear.

Avila, 55, who has lived in the tourist destination for 30 years, said the waves were unusually high. The city is bracing for waves up to 13 feet (4 meters) high.

Shops around Puerto Vallarta had boarded up their windows. It was not yet raining and some planned to open for a few hours before closing around midday.

Authorities in Puerto Vallarta have prepared shelters, although there are no evacuations yet. But south of the beach resort, people were evacuating from the towns of Zihuatlan and Melaque.

CONTAINER PORT CLOSED

Manzanillo, Mexico's main point of arrival for cargo containers, has been closed since late Sunday and about 13 container ships are stuck in the port.

An official said shipments that were held up because of the lock-down included 15,000 tonnes of sugar from Colombia, 16,000 tonnes of imported rolled steel and a shipment of iron pellets for domestic use.

Manzanillo handles about 750 containers of cargo a month and ships goods including cars, car parts, cattle, minerals and tequila to Asian and North American markets.

Depending on conditions, the port will reopen Wednesday or Thursday, the official said. Puerto Vallarta's port was also closed.

Mexico has no major oil installations in the Pacific.

The storm had slowed its advance and was moving toward the north-northeast near 5 miles per hour/7 kph), although the hurricane center said it could move slightly faster later on Tuesday.

The center expects Jova will turn toward the north on Tuesday night, after reaching the coast in the afternoon or evening. Hurricanes weaken over land.

A dangerous storm surge is likely to produce bad flooding along the coast when Jova makes landfall, the center said.

Rainfall of up to 12 inches/(30.5 cm) is forecast in parts of the states of Michoacan, Colima and Jalisco, possibly causing life-threatening flash floods and mudslides.

"A dangerous storm surge is expected to produce significant coastal flooding near and to the east of where the center makes landfall," the hurricane advisory said.

"Near the coast ... the surge will be accompanied by large and destructive waves," it said.

Puerto Vallarta Mayor Salvador Gonzalez said the resort was preparing shelters for residents that would be evacuated.

"There will be a lot of constant rain, which could hit the mountainous region around Puerto Vallarta," raising the danger of deadly landslides, Gonzalez said.

"But after a couple days of rain we'll be ready for the Pan-American Games," he said.

The games bring together athletes from across the Americas in Guadalajara, and some sport competitions will be held in Puerto Vallarta. (Writing by Elinor Comlay; Editing by Anthony Boadle and Bill Trott)