Why did Typhoon Bualoi cause such severe damage for Vietnam?

Before the storm hit, the National Center for Hydro-Meteorological Forecasting (NCHMF) was constantly providing updates, warning that Bualoi was moving at nearly twice the normal speed of typhoons, was intense, would have a wide impact area, and was likely to bring a combination of threats like high winds, heavy rains, river flooding, flash floods, landslides, and urban inundation.

Houses damaged by Typhoon Bualoi in Hoang Giang Commune of Thanh Hoa Province, central Vietnam, Sept. 29, 2025. Photo by Viet Hoang

On the rainfall aspect, it warned that between Sept. 27 and 30 the north and central regions between Thanh Hoa and Hue could get 100–300 mm, and even over 400 mm in some places.

In the Red River Delta, home to Hanoi, Hai Phong, Quang Ninh, Hung Yen, Bac Ninh, and Ninh Binh, it forecast 200–400 mm of precipitation, but 600 mm in some places.

In its report on the afternoon of Sept. 29, the Ministry of Agriculture and Environment said the forecasting and warnings were done "relatively well," enabling coordinated action by central and local authorities.

Despite all this the losses are substantial.

To put it in perspective, the most recent storm that made landfall in Vietnam, Kajiki, which hit the central Ha Tinh–Nghe An provinces on Aug. 25 with winds of 61-117 kph, left nine people dead or missing and 77 injured, and losses of an estimated VND2.9 trillion.

So why was Bualoi so deadly?

Mai Van Khiem, director of the NCHMF, said Bualoi was unusual in many respects.

It moved over the sea at 30–35 kph and slowed over land and lingered for 12–13 hours, longer than most storms to hit north-central Vietnam.

Le Ngoc Quyet, deputy director of the Ha Tinh Province Meteorological and Hydrological Station, said Bualoi was markedly different from other storms in the last 10 years.

Compared with Kajiki, or even Doksuri, which made landfall in 2017, Bualoi was more dangerous.

Both previous storms developed from tropical depressions off the Philippines, intensified as they moved toward Vietnam, and made landfall in central Vietnam.

Bualoi's winds did not just hit the shoreline as they pushed far inland. Mountain areas which rarely see damaging winds right after a storm made landfall, such as Huong Khe Commune of Ha Tinh Province, recorded storm-force gusts of around 90 kph or more.

Typhoon gusts toppled trees, and power lines sagged onto the roadway at Thien Cam Beach in Ha Tinh Province, Sept. 29, 2025. Photo by VnExpress/Duc Hung

Even in its late stage (day six), when Bualoi came ashore and faced substantial surface friction, it weakened slowly. It made landfall at 0:30 a.m. with winds of 103-117 kph; by 5 a.m. over Ha Tinh–Nghe An it eased to level 75–102; by 7 a.m. it dropped another level, and not until 10 a.m. did it fall to 61-74 kph. For three more hours along the Nghe An–Laos border it maintained at 61-74 kph, only becoming a tropical depression over upper Laos.

The storm battered inland areas for about 13 hours, nearly twice as long as Kajiki (seven hours)—leading to more severe destruction.

"In many years of forecasting, we've rarely seen a storm this strong linger so long over land. Watching the radar, everyone was tense because the storm showed no sign of weakening," Quyet said.

More dangerous still were tornadoes embedded in Bualoi.

At least ten twisters were recorded before, during, and after the storm in Hue City, Ha Tinh, Nghe An, Ninh Binh, Hung Yen, Quang Ninh, and Hai Phong. Though small—only tens to a few hundred meters in diameter—tornado winds can reach 180 kph, even over 300 kph. Because of their small scale, radar and satellites can hardly pinpoint a tornado’s exact position or shape to forecast it, and only warnings are possible.

In reality, at dawn on Sept. 29 a tornado tore through Khanh Thanh Commune of the northern Ninh Binh Province, which does not lie on the path of the storm, collapsing dozens of houses and killing nine people. Residents recalled that "in just a few minutes, the village was devastated, homes collapsed as if it was bombed."

The northern Hung Yen Province also reported two deaths that morning from this extreme phenomenon.

"The combination of strong winds, heavy rain, tornadoes, debris flows, flash floods, and landslides created a rare 'multi-hazard compound event' that exceeded the resilience of infrastructure and ordinary response scenarios," said a meteorological expert who wants to stay anonymous.

 

 

Why did Typhoon Bualoi cause such severe damage for Vietnam?

Storm Bualoi leaves 19 dead, 13 missing in Vietnam amid severe widespread damage

'Complacency' in response

In its Sept. 29 afternoon report, the environment ministry said that beyond harsh natural factors, losses from Bualoi were aggravated by "complacency." Some residents failed to fully and strictly follow instructions and advisories, leading to accidents such as returning to boats before the storm had cleared or traveling during gale conditions.

Many localities did not trim trees or brace and reinforce houses, offices, warehouses, and billboards, leading to widespread roof failures and breakage. "In some places, a segment of residents and businesses remained complacent and inattentive, with limited disaster-response skills... resulting in regrettable losses of life and property," the report said.

In central Quang Tri Province, although the storm made landfall in the province's north, lingered less time than in Ha Tinh, and rainfall was not extreme, there were still three deaths and eight missing. The victims had stayed on fishing boats moored on the Gianh River when the storm hit, despite an early sea-ban and calls for 145 boats with 810 fishermen to move to safe shelters. Large waves snapped mooring lines, capsizing boats and giving fishermen no time to escape.

Fisherman Sa Le, a survivor, recounted: "Thirteen of us had just finished dinner when the boat heeled sharply, water poured in, and within minutes it sank. I was lucky to swim ashore clutching a plastic can. Hired hands can only follow the captain's orders; there's no other choice."

Also noting complacency among some residents, Tran Duc Thinh, Chief of Office of the Ha Tinh Steering Committee for Natural Disaster Prevention and Search & Rescue and head of the provincial Irrigation Sub-Department, said preparations before and during the storm were thorough, with thousands of households evacuated.

However, fatalities and injuries still occurred—often when people who returned to their homes to repair damage.

VnExpress observations in some coastal communes of Nghe An and Ha Tinh found that before landfall many residents, owners of shrimp ponds and fish rafts, refused to take shelter, lingering to move assets.

"Many incidents did not occur at the storm's peak but during preparations or in post-storm repairs, all due to poor safety awareness," a commune leader in Ha Tinh said.

The Ministry of Agriculture and Environment said that to reduce typhoon losses, beyond upgrading dikes, power grids, and housing, communities must be educated in disaster-response skills. In particular, scenarios should be developed for new extreme phenomena such as tornadoes, and for urban flood prevention in places rarely struck by a storm's eye but prone to torrential rain, like Hanoi.

"People are used to coping with windstorms, but Bualoi is a fresh reminder that no preparation is excessive when natural hazards are increasingly unpredictable," said Le Ngoc Quyet, Deputy Director of the Ha Tinh Meteorological and Hydrological Station.