An area of low pressure is developing around Luzon, in the Philippines, and is expected to move westward across the northern part of the South China Sea on Tuesday, according to the Hong Kong Observatory. Intermittent showers are likely to affect Hong Kong over the next nine days.
The Observatory also said another area of low pressure may develop over the eastern part of the Philippines towards the weekend, but it is unclear whether it will affect Hong Kong.
A tropical depression was first reported by the Joint Typhoon Warning Center on Sunday. It will be closest to the city on Tuesday as it moves westwards, before passing Hainan and moving across to Laos.
The Strong Monsoon Signal has been in force since Saturday morning as a ridge of high pressure brings an easterly airstream to the coast of Guangdong. The Observatory said there will be sunny intervals and one or two isolated showers on Monday afternoon, with a mainly cloudy night.
A few showers are expected over the next two days, the Observatory said.