Pedestrians wade through rainwater while crossing a road during heavy rainfall in Hong Kong on Aug. 5, 2025. Photo: VCG

On Tuesday, torrential rain battered multiple cities across southern China. Shenzhen in Guangdong Province issued its first citywide red rainstorm alert since 2018, while Hong Kong shattered the highest single-day rainfall record for the month of August since 1884.
Affected by an intense monsoon, rainfall intensified across Shenzhen from Monday night through Tuesday morning. Between 8 pm Monday to 5 am Tuesday, the city recorded an average cumulative rainfall of 84 millimeters, with a maximum accumulation of 208.3 millimeters and peak hourly precipitation of 99 millimeters, according to the Shenzhen Meteorological Observatory.

The observatory extended the red rainstorm alert to the entire city at 4:13 am on Tuesday, marking the first citywide red alert since Typhoon Mangkhut in 2018. It also said that the rainstorm features prolonged duration, substantial cumulative precipitation, exceptionally high short-term precipitation, extensive coverage and high disaster potential.

Meteorological authorities urged relevant departments to prioritize preparations against rain-induced disasters, such as urban flooding, mountain torrents, landslides, mudflows and ground subsidence.

A resident surnamed Wu from Longgang district in Shenzhen described Tuesday morning's torrential downpour as unprecedented, adding that "the water had risen above vehicle tire levels." "This is the most severe flooding I've seen in over a decade," she told the Global Times. 

Wu also said that local fire and rescue teams have carried out emergency operations, and that the water level has since significantly decreased.

Huizhou in South China's Guangdong Province raised its rainstorm alert to red at 2:28 am on Tuesday, mandating the suspension of classes, work, production, transportation and business operations across all districts starting 6 am.

All citizens were advised to remain indoors in secure structures, according to local meteorological authorities.

In addition to Guangdong, the Hong Kong and Macao special administrative regions were also battered by heavy downpours on Tuesday.

The observatory issued the black rainstorm warning at 5:50 am on Tuesday. It remained in effect for 11 hours and was replaced by a yellow rainstorm warning at 5:05 pm and finally cancelled at 6:15 pm, local media outlet RTHK reported.

The black rainstorm warning represents the highest level, indicating that widespread areas of Hong Kong have recorded or are expected to experience rainfall exceeding 70 millimeters per hour, which is likely to continue, according to the observatory.

The observatory also issued a black rainstorm warning on Monday evening, with the alert remaining in effect for several hours. It marked the first time since records began in 1998 that four black rainstorm warnings had been issued within a single week, the observatory said.

By 2 pm, rainfall had reached 355.7 millimeters, shattering the highest single-day rainfall record for the month of August since 1884, RTHK reported, citing data from the observatory.

Rainwater gushes out from a drainage channel in Wo Yi Hop Road in the Hong Kong Special Administrative Region on August 5, 2025. The Hong Kong observatory issued a black rainstorm warning indicating that the region is experiencing massive rainfall. Photo: VCG

Heavy rains in Hong Kong and Shenzhen this time are mainly due to the influence of the southwest monsoon. Warm and moist southwest airstreams have been continuously pumped over the Pearl River Delta, giving rise to relatively extreme rainfall, Ma Jun, director of the Institute of Public and Environmental Affairs, told the Global Times on Tuesday.

At a car park in Yau Yue Wan Village of Po Lam, severe flooding occurred, with water levels reaching as high as the roofs of taxis in the worst-hit areas, a Hong Kong-based news website reported. Approximately 20 vehicles in the car park, among which around nine were submerged to the height of their roofs or even windshields.

Lai Chi Kok's Kau Wa Keng village experienced temporary flooding, with villagers reporting waist-deep waters at the peak. While conditions have significantly improved in the village, some open drainage channels remain inundated, TVB News said.
Hongkong Post also announced the suspension of all post offices and delivery services due to the black rainstorm warning.

The Macao Meteorological and Geophysical Bureau also issued a black rainstorm warning at 8:18 am and extended it until 12 noon.

Macao's education authority required the suspension of morning classes for secondary education, and full-day suspension for primary education, early childhood education and special education be suspended throughout the day.

Increasing afforestation, strengthening the protection of natural wetlands and enhancing sponge city construction are among the ways to alleviate urban waterlogging in cities with dense buildings, the expert said.