The Hong Kong Observatory has said it will consider raising the No 3 typhoon warning signal on Friday as a tropical depression in the South China Sea edged closer to the city.

In a weather bulletin, the observatory issued the Standby Signal, No. 1 at 7:40 am Thursday as the tropical depression came within 800 kilometers of the territory.  

It added that the tropical depression will intensify gradually and move in the general direction of Hainan Island, maintaining a distance of 500 km or more from Hong Kong.

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“Depending on the change of its intensity, the distance of its strong winds from the Pearl River Estuary and local wind conditions, the observatory will assess the need for issuing the Strong Wind Signal, No. 3 tomorrow,” reads the HKO bulletin.

As of 9 am Thursday, the tropical depression over the central part of the South China Sea was estimated to be about 600 km south-southwest of Hong Kong and was expected to move at about 18 km per hour in the general direction of Hainan Island.

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The observatory said local winds will strengthen gradually on Friday and the weather will become unsettled.

It added that there will be swells and members of the public should stay away from the shoreline and avoid water sports.