Thunderstorms began in western Hanoi around 15h, affecting areas such as Chuong My, Phu Nghia, Quoc Oai, and Thach That. The heavy rain then spread to inner-city wards. By approximately 16h30, the sky had darkened, and intense downpours covered the central area, coinciding with the evening rush hour.

According to Hanoi Drainage Company Limited, rainfall measurements within a single hour were exceptionally high in several areas: Tay Mo recorded 116 mm, Cau Giay 84 mm, and Dai Mo 71 mm.

The rapid accumulation of rain in a short period led to widespread flooding and prolonged traffic jams on many roads. Affected routes included Nguyen Trai, Cau Giay, Pham Hung, Ho Tung Mau, National Highway 6, and Ring Roads 1, 2, 3, and Minh Khai.

The drainage company staff on duty at Phung Hung street. *Photo: Vo Hai*

The rain resulted from a tropical convergence zone passing over the southern Red River Delta and North Central region. The Northern Hydro-Meteorological Station warned that Hanoi and neighboring areas would continue to experience moderate to heavy rain over the next 1-3 hours. Total rainfall is expected to be between 30-50 mm, with some localized areas receiving more. This rainfall could cause localized flooding on many streets, typically 10-30 cm deep and lasting about 20-30 minutes, though some areas may experience longer periods. Certain routes could see deeper flooding, reaching 20-40 cm.

Areas at risk of flooding span across numerous wards. In the central district, streets such as Phung Hung, Bat Dan, Duong Thanh, Trang Tien - Hang Bai, Nguyen Huu Huan, Tong Dan, Dinh Liet, and Ta Hien - Luong Ngoc Quyen are particularly vulnerable.

In the western part of the city, warned locations include Tran Binh, the pedestrian underpass beneath Thang Long Boulevard, the area in front of My Dinh stadium; Hoa Bang, Xuan Thuy, Phan Van Truong, Pham Hung, Ton That Thuyet, Duy Tan; Yen Hoa, Nguyen Khang, Duong Dinh Nghe, and Le Van Luong.

Southern Hanoi faces flood risks on Giai Phong, Tan Mai, Nguyen Chinh, Linh Nam, Dinh Cong, Nguyen Xien, Linh Dam, Le Trong Tan, Van Phuc, Nguyen Van Troi, To Huu, and Chien Thang streets.

Residents are advised to monitor rain developments, avoid deeply flooded areas, and proactively choose appropriate routes.

Gia Chinh