The Hong Kong Observatory issued the amber rainstorm warning signal before noon on Sunday as heavy rain lashed parts of the territory.

The observatory said in a weather bulletin at 11:10 am that heavy rain has fallen or was expected to fall generally over city, exceeding 30 millimeters in an hour.

“Heavy rain may bring about flash floods. People should stay away from watercourses,” the HKO said.

It said showers and thunderstorms associated with a trough of low pressure were affecting the coast of Guangdong and the northern part of the South China Sea.

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The observatory also extended the thunderstorm warning, issued at 8:30 am, to 1 pm.

It added that the weather in Hong Kong later on Sunday was expected to be mainly cloudy with showers and a few squally thunderstorms.