Hong Kong was lashed by intense overnight downpours that triggered a red rainstorm warning, flash flooding in the northern New Territories and a special landslip alert in the small hours of Wednesday.

The Hong Kong Observatory hoisted the red rainstorm signal at 2.40am, warning that more than 50mm of rain had fallen in some districts and that conditions could deteriorate further. Shortly after 5.15am the warning was downgraded to amber, but forecasters cautioned that heavy showers and squally thunderstorms would continue through the morning, particularly over the northern fringe of the city.

Meteorologists said the heaviest rain was concentrated in the North district and around the SAR demarcation line with Shenzhen, with Sheung Shui, Ta Kwu Ling and Sha Tau Kok singled out as hotspots. 

Between about 7.45pm and 9.45pm on Tuesday, some parts of the North district recorded more than 120mm of rain, while Ta Kwu Ling alone saw over 70mm in a single hour. The Observatory issued a separate flooding alert for the northern New Territories at 9.45 pm and a special landslip warning overnight, advising residents in hilly and low‑lying areas to stay alert and avoid slopes and swollen streams.

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The Drainage Services Department said it activated 90 emergency response teams to inspect drains and clear blockages as the rain intensified. By 3 am, seven flooding cases had been confirmed, six of which were quickly resolved; work was continuing on the remaining incidents in Ping Che and Fanling, where the department deployed two large drainage robots to help move water and debris.

Local media reported that floodwater in some village roads and underpasses in the northern New Territories reached knee height, temporarily stranding vehicles and prompting police to close sections of carriageway. A minibus in Sheung Shui was left stuck in roughly half a metre of water at one point, although no serious injuries were reported.

In urban Kowloon and Hong Kong Island, the impact was less dramatic but still disruptive, with commuters waking to intense showers, water pooling on some streets and warnings of slippery road conditions during the morning rush hour. 

The amber warning was cancelled at 9:30 am, but officials reminded the public to monitor weather bulletins and beware of further heavy bursts of rain and possible flooding in poorly drained areas.