Slow-moving Typhoon Narra raises flood, landslide risks in northern Vietnam
VOV.VN - Typhoon Narra is moving very slowly over the northern Gulf of Tonkin as heavy rain continues across northern Vietnam, with already saturated ground and rising river and stream levels increasing the risk of flooding, flash floods and landslides.
Typhoon Narra formed over the Gulf of Tonkin after a tropical depression strengthened into a storm. As of the morning of August 23, it was moving at only around 3 kmh, with maximum sustained winds of 62-74 kmh and gusts of up to around 100 km/h.
Narra is forecast to remain slow-moving over the northern Gulf of Tonkin on August 23 before potentially changing direction. Its slow progress means its circulation could continue producing rainfall over northern Vietnam for an extended period.
The main concern on land is no longer simply the storm’s winds, but the combination of prolonged rainfall, rising water levels and the storm’s slow movement, which could allow rain to persist over areas that have already been affected by several days of downpours.
Many parts of the north have already experienced several consecutive days of rain. In some areas, the ground is saturated and water levels in rivers and streams are continuing to rise, increasing the potential for rain-related disasters.
Heavy rain and rising water levels
From August 22 through the end of August 23, northeastern Vietnam, and parts of Phu Tho and Thanh Hoa provinces are forecast to receive widespread rainfall of 70-150 mm, with isolated totals exceeding 300 mm.
Rainfall in Quang Ninh and Hai Phong could reach 200-300 mm, with isolated areas receiving more than 500 mm. Lang Son and Bac Ninh could see 150-250 mm, with isolated totals exceeding 400 mm.
Water levels are rising rapidly on several rivers in northeastern Vietnam. At 3 a.m. on August 23, the Luc Nam River at Luc Nam station reached 6.28m, just 2cm below alert level 3, the highest flood alert level. Meanwhile, the Thuong River at Phu Lang Thuong station stood at 5.23m, only 7cm below alert level 2. Over the previous eight hours, water levels at the two stations had risen by about 59cm and 62cm, respectively.
The weather agency forecasts that water levels on the lower Luc Nam River will continue to rise in the coming hours and could exceed alert level 3, while the Thuong River could rise above alert level 2. From August 23 to 25, floodwaters on several rivers in northeastern Vietnam are expected to remain high.
With river and stream levels already rising, further heavy rain could increase flooding in low-lying areas, urban centres and communities near waterways.
In mountainous areas, additional rain falling onto already saturated ground could sharply increase the risk of flash floods, landslides and ground subsidence on steep slopes.
The storm’s circulation could also bring rain to a much wider area of northern Vietnam. Hanoi is expected to see moderate to heavy rain and thunderstorms as well.
Cumulative rainfall adds to disaster risks
What makes the current situation particularly concerning is the cumulative impact of several days of rain.
When soil is already saturated, another period of heavy rainfall can quickly increase runoff into rivers and small streams, triggering flash floods in steep terrain. In low-lying areas, water flowing downstream can also cause flooding to worsen rapidly.
Residents in areas near rivers and streams, low-lying communities and locations vulnerable to landslides should therefore closely monitor warnings from local authorities.
The Prime Minister has already instructed local authorities to review high-risk areas and proactively evacuate residents, particularly from places vulnerable to deep flooding, flash floods and landslides.
Authorities have also been asked to deploy personnel to control traffic at low-water crossings and on roads vulnerable to flooding or landslides, strengthen safety measures for dykes, reservoirs and other infrastructure, and remain ready to assist residents.
Slow movement keeps the risk elevated
The defining feature of Typhoon Narra is its very slow movement. At around 3 kmh, the storm is moving through an area where northern Vietnam has already experienced prolonged rainfall.
That means the storm does not necessarily need to make a direct landfall to pose a serious threat. Its circulation could continue to produce prolonged heavy rain, particularly across northeastern areas.
The storm’s track and intensity may still change in the coming days, making continued monitoring important, especially in areas already experiencing heavy rain and rapidly rising water levels.
For residents, the key question is no longer simply how strong the storm is, but how slowly it moves, how long the rain continues and how high river and stream levels rise. When these factors occur together, the risks of flooding, flash floods and landslides can increase rapidly.
PM orders evacuation from high risk areas as typhoon Narra forms
VOV.VN - With typhoon Narra forming over the Gulf of Tonkin and days of heavy rain and flooding in the northern and north-central regions, the Prime Minister has ordered local authorities to review high-risk areas and proactively evacuate residents, particularly those facing deep flooding, flash floods and landslides.
