Tourists stroll along the seafront in Puerto Vallarta
Tourists stroll along the seafront in the Mexican city of Puerto Vallarta hours before the expected arrival of Hurricane Lidia AFP

Hurricane Lidia made landfall Tuesday on Mexico's Pacific coast as an "extremely dangerous" Category 4 storm, threatening to bring flooding and mudslides, forecasters said.

President Andres Manuel Lopez Obrador said earlier that civil protection personnel were on alert and around 6,000 members of the armed forces had been deployed to help residents.

Lidia came ashore near the popular beach resort of Puerto Vallarta, packing maximum sustained winds of around 140 miles (220 kilometers) per hour, the US National Hurricane Center (NHC) said.

"Life-threatening winds and flooding rainfall spreading inland over west-central Mexico," it said in a bulletin.

Lidia rapidly strengthened to the second-highest category on the five-step Saffir-Simpson scale before reaching land, according to the NHC.

In Puerto Vallarta -- a major destination for Mexican and foreign tourists -- shopkeepers earlier boarded up windows and piled up sandbags in case of flooding.

"It's coming straight at us," said Luis Ramos, 29, who was racing to protect the bar where he works from potential damage.

"It's better to be safe than to rush to do it later," Felipe Pinto, head of maintenance at a hotel, told AFP as his team put out sandbags.

School classes were suspended in some areas and residents were urged to take shelter.

Lidia was expected to bring rainfall of up to 12 inches (30 centimeters) to Nayarit, Sinaloa and Jalisco states, it said.

"These rains will likely produce flash and urban flooding, along with possible mudslides in areas of higher terrain near the coast," the NHC warned.

"A dangerous storm surge is expected to produce significant coastal flooding near and to the south of where the center makes landfall. Near the coast, the surge will be accompanied by large and dangerous waves," it added.

Hurricanes hit Mexico every year on both its Pacific and Atlantic coasts, usually between May and November.

Just this week, Tropical Storm Max left two people dead and dozens of houses flooded in the southern state of Guerrero, one of the country's poorest regions, authorities said Tuesday.

Max made landfall on Monday, causing a river to overflow before dissipating.

One person drowned trying to protect livestock and another died in a road accident during the storm, civil protection official Roberto Arroyo told AFP by telephone.

In August, storm Hilary, which at one point was a Category 4 hurricane, caused one death and damaged infrastructure as it hit the northwestern state of Baja California.

Scientists have warned that storms are becoming more powerful as the world gets warmer with climate change.

Workers place sandbags outside a shop in Mexico's Puerto Vallarta
Workers place sandbags outside a shop in Mexico's Puerto Vallarta to protect against possible flooding AFP
Shopkeepers in Puerto Vallarta boarded up windows
Shopkeepers in Mexico's beachside city of Puerto Vallarta boarded up windows before Hurricane Lidia made landfall AFP