The National Center for Hydro-Meteorological Forecasting announced at 4:50 on 18/9 that satellite images, lightning location data, and weather radar indicate convective clouds are active in the Huong Son and My Duc areas.

Over the next 3 hours, this thunderstorm cloud system is forecast to continue bringing showers and thunderstorms to Huong Son, My Duc, Hong Son, Hoa Xa, Gia Lam, and Bat Trang. During these thunderstorms, there is a possibility of tornadoes, lightning, and strong gusts.

Convective cloud system in Hanoi's outskirts. Photo: Department of Meteorology and Hydrology.

This warning follows several days of widespread heavy rain in Hanoi. However, since last night, the rain has eased, floodwaters in inner-city areas have begun to recede, and by this morning, traffic has largely returned to normal.

From 14/9 to 17/9, the combined effects of a tropical depression and a tropical convergence zone brought continuous rain to the city, with many areas recording over 400 mm of rainfall. The rain on the night and early morning of 17/9 caused many streets to flood over 50 cm deep, leading to traffic chaos.

By the afternoon of 17/9, rain decreased, but flood levels on some rivers remained high. The Tich River at Kim Quan reached 8,81 m, 0,41 m above alarm level three; the Bui River at Yen Duyet reached 7,54 m, 0,54 m above alarm level three. The floods submerged about 2,200 homes in the outskirts, nearly 19 km of roads, and necessitated the evacuation of residents in some areas.

According to forecasts, on 18/9, the Northern region will continue to experience scattered showers and thunderstorms, with rainfall generally between 10-30 mm, and localized areas exceeding 50 mm. Meanwhile, from Thanh Hoa to Ha Tinh, rainfall will be 20-50 mm, with localized areas exceeding 80 mm.

From the night of 18/9 to 19/9, heavy rain will shift south to the area from Nghe An to Hue City, with general rainfall of 30-60 mm, and localized areas exceeding 100 mm. Meteorological agencies warn of a risk of intense rainfall exceeding 100 mm within 3 hours.

Additionally, on the afternoon and evening of 18/9, the Southern region will have thunderstorms; the Central Highlands, Khanh Hoa, and eastern Lam Dong will experience showers. Across the country, during thunderstorms, there is a possibility of tornadoes, lightning, hail, and strong gusts.

Gia Chinh