In two hours from 2 p.m. to 4 p.m. on Sunday, the weather station on Lang recorded rain levels at 138 mm, which exceeded the previous record at 132.5 mm on June 18, 1986, the National Center for Hydro-Meteorological Forecasting said.
In the same time frame, Cau Giay District saw the most rain at over 170 mm, followed by Tay Ho District at 150 mm, Hoang Mai at 130 mm and Ba Dinh, Thanh Xuan and Thanh Tri districts at 100 mm, according to weather stations across the capital.
Downpours have submerged over 30 streets in Hanoi, with parts even 60-70 cm deep, paralyzing traffic.
A representative of the Hanoi Drainage Company said high-intensity rains may overload the city's water drainage systems, causing local inundations.
Hundreds of employees were dispatched Sunday afternoon to patrol flooded areas, warning people and clearing the drains of trash and debris, as well as opening up penstocks in lakes like Bay Mau, Dam Chuoi and Ho Me to ensure that they could handle future rains.
From 2021 to 2025, quick urbanization speed and high population density have necessitated the development of water drainage and treatment system, especially in areas like Ha Dong, Long Bien districts and the outlying Son Tay Town, according to the Hanoi People's Committee.
The downpours on Sunday in Hanoi was the result of a low-pressure area, which also brought rain to Son La and Hoa Binh Provinces. Until Tuesday, rains would continue in mountainous and midland areas of the north, with rain levels at up to 150 mm. Starting Monday night, rain would come to regions from Thanh Hoa to Thua Thien-Hue in the central region, meteorologists said.