Heavy rainfall inundates Hong Kong, following series of alert notifications for storms
Historic Rainfall Strikes Hong Kong: A Day of Unprecedented Flooding
On August 5, 2025, Hong Kong experienced its heaviest daily rainfall ever recorded, with a staggering 358.8 millimeters (14.1 inches) of rain measured at the Hong Kong Observatory headquarters [1][3]. This torrential downpour broke the previous record, set in 1884, and lasted for over 11 hours under the highest-level black rainstorm warning.
The impact of this intense rainfall was significant. Extensive flooding of roads and urban areas occurred, causing at least 14 landslides across the city, including dangerous locations such as Po Shan Road [1]. The Hong Kong International Airport experienced severe disruptions, with over 431 flights delayed and 12 canceled [1]. Public transport was also affected, with some metro exits closed, and courts adjourned all hearings. The Hong Kong Gold Exchange even closed an open market session due to the floods [1].
Government agencies and officials took numerous precautions to mitigate the impact of this historic event. The Hong Kong Observatory issued and maintained a black rainstorm warning—the highest level—for nearly 12 hours, advising residents to stay indoors [1][3]. The city's number two official, Eric Chan, urged the public to stay alert and advised employers to consider flexible working arrangements prioritizing employee safety [1].
The Observatory also announced plans to enhance its AI weather prediction models to improve future forecasting of extreme rainfall [5]. Additionally, the government debated the criteria for declaring "extreme conditions" to better manage public response during natural disasters, aiming to clarify when workers can safely return after warnings are lifted [3]. Residents were also urged to avoid outdoor activities such as hiking due to risks of landslides and floods following the rainfall [4].
Emergency services were stretched thin, with the Drainage Services Department identifying 25 cases of flooding as of Tuesday afternoon [5]. Emergency room service at the Queen Mary Hospital was affected for around two hours due to flooding [1]. Small boats have capsized off the coast of the eastern Tseung Kwan O district [1].
In neighbouring Shenzhen, a tech hub, a "red" rainstorm warning was issued earlier in the day, the first time since 2018 [1]. Schools have been suspended, and temporary shelters have been opened in both cities to accommodate those affected by the floods.
As scientists warn that the intensity and frequency of global extreme weather events will increase as the planet continues to heat up due to fossil fuel emissions, China aims to become carbon-neutral by 2060 [1]. This historic rainfall event serves as a stark reminder of the urgent need for action to combat climate change and prepare cities for the challenges of the future.
- The unprecedented flooding in Hong Kong, caused by the record-breaking rainfall, highlights the significance of studying environmental science and climate-change, given the increasing frequency of extreme weather events due to global warming.
- As scientists predict an uptick in the intensity of climate-change related extreme weather events such as this, it becomes crucial for countries like China, aiming to attain carbon-neutrality by 2060, to invest in advancements in weather prediction models and environmental-science, ensuring better preparedness for future disasters.
