Bualoi made landfall in central Vietnam late Sunday, packing winds of 130 kilometres (80 miles) per hour, and remaining over land for almost 12 hours.

The duration was "very rare" as compared to other typhoons, said Mai Van Khiem, head of the National Centre for Hydro-Meteorological Forecasting, on Tuesday.

"This typhoon -- the tenth that hit Vietnam this year -- was a serious natural disaster, bringing a combination of strong winds, huge flash floods and widespread flooding," Khiem said.

By Tuesday, the typhoon and its aftermath, including a whirlwind in the north on Monday, had killed 19 people and injured more than 80, according to a report from the environment ministry.

A search for 21 others was ongoing -- including several sailors whose fishing vessels became unmoored by strong winds and currents.

More than 100,000 houses were damaged, and around 2,700 families were stranded in central Ha Tinh province, the ministry said.

"I have not experienced such a strong typhoon in several decades," Le Hong Luyen, 62, from Nghe An province told AFP. "My house and garden are all flooded."

The storm also devastated 225 square kilometres of rice and other cropland, uprooted more than 10,000 trees and downed electrical poles, causing power outages in several central areas on Tuesday.

Disaster and weather authorities were continuously updating alerts on Tuesday on rising river levels and possible landslides in mountainous areas.

The Southeast Asian nation is usually hit by up to 10 storms annually, but forecasters have warned of two to three more this year.

Scientists say human-driven climate change is turbocharging extreme weather events like typhoons, making them ever more deadly and destructive.

Storms in Vietnam have caused $371 million in damage from January to August, triple the amount from the same period last year, the General Statistics Office (GSO) said.

Typhoon Yagi killed hundreds of people in Vietnam in September last year and caused economic losses worth $3.3 billion.

The capital Hanoi also suffered heavy rain from late Monday, with widespread flooding disrupting traffic.

"The floodwater reached almost the top of my motorbike. It was a terrible morning. My bike got damaged," said Hanoi resident Tran Thanh Huong, who never reached her office after almost two hours of trying.

Typhoon Bualoi also battered small islands in the centre of the Philippines last week, unleashing floods, killing 27 people and forcing 400,000 to evacuate.