The Observatory issued the Standby Signal No 1 at 12:40 am on Wednesday, as a broad area of low pressure over the central part of the South China Sea intensified into a tropical depression.

The tropical cyclone is expected to maintain a distance of about 700 kilometres from Hong Kong today and tomorrow, then move in the general direction of Hainan Island and the vicinity of the coast of western Guangdong afterwards.

At 11 pm on Tuesday, the tropical depression was centred about 250 kilometres southeast of Xisha. It is forecast to move west-northwest at about 10 kilometres per hour across the central part of the South China Sea.

Depending on its distance from Hong Kong and its rate of development, the Observatory will assess the need to issue a higher tropical cyclone warning signal in the latter part of Thursday (12 June) to Friday (13 June).

With the tropical cyclone edging closer, the weather will become windy with occasional heavy squally showers in the latter part of this week, and there will be swells.