The Hong Kong Observatory on Thursday morning issued its second-highest rainstorm warning signal as heavy rains battered the city, leading to the suspension of morning classes.

The observatory raised the red signal at 5:05 am, warning that heavy rain, exceeding 50 millimeters in an hour, was expected to fall or had already fallen over the territory before downgrading the warning to amber – the third-highest alert – at 9:20 am.  

Under the influence of a trough of low pressure and an active southerly airstream, heavy rainfall even exceeded 100 mm over the eastern part of the territory.

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The Education Bureau said all classes in morning schools and whole-day schools would be suspended. Schools should implement contingency measures and ensure the safety of students who have already arrived on their premises, it added.

However, afternoon school classes will proceed as usual as the amber warning was eventually canceled at 10:15 am.

In a weather advisory, the HKO said rain has been particularly heavy in Po Toi Island, which may cause landslides.

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“Pay special attention to landslide risk and stay away from slopes. If landslide occurs nearby, leave immediately and call the police under safe conditions,” the advisory reads.

People who have to travel should carefully consider the weather and road conditions and take necessary precautions, it added.

The Social Welfare Department also advised members of the public not to take their children or family members to units providing child care center services and after-school care programs, elderly services centers, day pre-school rehabilitation services units, integrated vocational training centers and day activity centers.