The Hong Kong Observatory issued a second Black Rainstorm Warning on Thursday as heavy downpours triggered flooding across the city [1, 2].
These extreme weather conditions forced the immediate closure of schools and disrupted daily transit, signaling a severe risk to public safety in high-risk areas. The intensity of the storms necessitated urgent shelter advisories for residents to avoid flash floods.
The warning followed forecasts of heavy rain exceeding 70 mm in a single hour [3]. This specific meteorological event marked the second Black Rainstorm Warning Signal issued within the calendar year [1]. In a rare occurrence, two black rainstorm warnings were issued in a single day [2].
Flooding was most severe in the New Territories region, where persistent rainfall overwhelmed drainage systems [2, 3]. Local authorities said residents should remain indoors and avoid all unnecessary travel while the signal remained active. The sudden surge in water levels created hazardous conditions for commuters and pedestrians, particularly in low-lying urban sectors.
Emergency services monitored the situation as the city grappled with the persistent rainfall. The Black Rainstorm Warning is the highest level of rain alert in Hong Kong, intended to warn the public of extremely heavy rain that may cause severe flooding [1].
Officials said they continued to monitor the weather patterns to determine when it would be safe to resume normal operations. The disruption coincided with the Tuen Ng Festival, complicating local celebrations, and public gatherings [2].
“Two black rainstorm warnings were issued in one day”
The issuance of two black rainstorm warnings in a single day highlights an increasing volatility in regional weather patterns. For a densely populated urban center like Hong Kong, such extreme precipitation events test the limits of municipal drainage infrastructure and emergency response protocols, particularly in the New Territories.
