Pham Thi Thanh Hoa, a forecaster at Vietnam’s National Center for Hydro-Meteorological Forecasting, has provided an update on rainfall, flash floods and landslide risks across northern and north-central Vietnam.

Between 7 a.m. and 4 p.m. on Sept. 16, rainfall across the northern midlands and delta, as well as areas from Thanh Hoa to northern Nghe An, generally ranged from 20-50mm.

Some locations recorded more than 100mm, including Trung Ha Commune in Thanh Hoa with 160mm, Thuong Coc Commune in Phu Tho with 76mm and Binh Thanh Commune in Thai Nguyen with 61mm.

From the evening of Sept. 16 through Sept. 17, Lao Cai, Tuyen Quang, Phu Tho, Thai Nguyen, Bac Ninh, Hung Yen, Ninh Binh, Hanoi, Thanh Hoa and Nghe An are forecast to experience moderate to heavy rain, with localized torrential downpours and thunderstorms.

Rainfall is expected to range from 50-90mm across these areas, with some locations receiving more than 200mm.

Lang Son, Hai Phong, Quang Ninh and southern Son La are forecast to receive 30-50mm, with localized totals exceeding 90mm.

Forecasters have warned of particularly intense bursts of rain exceeding 100mm within three hours.

In Hanoi, heavy rain is expected throughout the night of Sept. 16 and during Sept. 17, with widespread totals of 40-70mm and more than 100mm possible in some areas.

Elsewhere, Lai Chau, Dien Bien, Cao Bang and northern Son La, along with areas from Ha Tinh to Quang Tri, are expected to see scattered showers and thunderstorms overnight and through Sept. 17.

Rainfall in these areas is forecast at 15-30mm, with localized totals exceeding 70mm.

On the evening of Sept. 16, developing convective clouds are also expected to bring scattered showers and thunderstorms from Hue southward to Lam Dong and across southern Vietnam.

Rainfall will generally range from 10-30mm, with localized downpours exceeding 50mm.

Heavy rain across northern Vietnam, Thanh Hoa and Nghe An is forecast to gradually ease from the night of Sept. 17.

The downpours could cause localized flooding in low-lying areas, disrupting traffic and daily life.

Flooding on several rivers remains complicated

As of the afternoon of Sept. 16, floodwaters on the Boi River in Phu Tho were receding but remained above the highest, Level 3 warning threshold.

The Hoang Long River in Ninh Binh, meanwhile, was rising and had also exceeded Level 3.

In Thanh Hoa, the upper reaches of the Buoi River were rising above Level 3, while the lower reaches were also rising but remained below that threshold.

The Am River at the Lang Chanh monitoring station was likewise above Level 3.

Over the next 24 hours, flooding on the Boi River is expected to continue receding to between Level 1 and Level 2.

The Hoang Long River, by contrast, is forecast to continue rising above Level 3 before changing slowly.

In Thanh Hoa, the Buoi River is forecast to continue rising above Level 3, while the Am River is expected to fall to Level 1.

Floodwaters along the middle reaches of the Ma River are expected to continue rising and exceed Level 2.

Very high risk of flash floods and landslides

Authorities have warned of a very high risk of flash floods and landslides in Son La, Phu Tho, Lao Cai, Tuyen Quang, Thai Nguyen, Quang Ninh, Thanh Hoa and Nghe An.

The danger is concentrated in mountainous areas, on steep terrain and in locations that have already experienced prolonged heavy rainfall.

Residents are being urged to exercise particular caution around rivers and streams, at the foot of embankments and slopes, and in areas susceptible to landslides.

Hanoi police help residents evacuate flooded areas

Hanoi police said on Sept. 16 that officers in My Duc and Hong Son communes had deployed personnel and coordinated with local authorities and other agencies as heavy rain caused flooding in several areas.

Their work focused on protecting residents, property and agricultural land.

In My Duc Commune, police officers went directly into flooded areas to identify households in dangerous locations, help residents move property and assist with evacuations to safer ground.

Officers also went into rice fields to help farmers harvest crops in areas at risk of being inundated.

In Hong Son Commune, rising water on the My Ha River flooded agricultural areas.

Local police worked with other forces and residents of Phu Son Village to reinforce embankments, address the risk of water overflowing and protect dikes and farmland.

Bao Anh - Tien Dung