Rainstorm warnings cancelled after day of downpours and disruption in Hong Kong

All rainstorm warnings were cancelled at 3pm on Wednesday after hours of rain had drenched Hongkongers and slowed traffic to a crawl.

The Hong Kong Observatory had issued the black rainstorm signal, its highest warning, earlier in the day, at 11.30am, following an amber signal at 6.40am and red at 9.15am.

The black warning meant heavy rain had fallen or was expected to fall over Hong Kong, exceeding 70mm an hour, and was likely to continue.

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The black signal later gave way to an amber one at 12.30pm, before all warnings were cancelled at 3pm.

All classes at schools across Hong Kong had been suspended, the Education Bureau said. Morning and whole-day schools already in session were told to continue until the end of school hours.

The bureau urged schools to implement contingency measures to ensure the safety of students. Staff were asked to ensure conditions were safe before allowing students to return home.

The Hong Kong Examinations and Assessment Authority said oral exams in English language scheduled for 3pm for the Diploma of Secondary Education would be postponed or cancelled, along with international and professional examinations commencing before 4pm.

Alternative arrangements would be announced at a later date, it said.

Amid the downpours a China Eastern Airlines flight slid off the runway while landing at Hong Kong International Airport at about 10.50am. The plane managed to come to a stop on grass next to the runway. No casualties were reported.

The Social Welfare Department said all centres for child care, elderly services and day rehabilitation would remain open. The public could contact the centres to arrange safe return home for their children and family members if necessary.

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Thundery showers associated with a trough of low pressure were affecting the coastal areas of Guangdong.

Locally, more than 50mm of rainfall was recorded over many areas in Hong Kong on Wednesday morning, with rainfall exceeding 100mm in Kwai Tsing and Sham Shui Po.

A thunderstorm warning was issued at 4.40am and was set to remain in force until at least 1pm.

The Observatory had warned there would be flooding in some low-lying and poorly drained areas.

The weather on Wednesday was expected to remain cloudy with occasional heavy showers and squally thunderstorms before gradually becoming fine in the next few days.