At 4pm, Tropical Storm Cempaka was estimated to be about 180 kilometers southwest of Hong Kong and is forecast to move north slowly, gradually edging closer to the vicinity of the area to the west of the Pearl River Estuary.
According to the present forecast track, Cempaka will edge gradually close to the coast of western Guangdong. Winds in the vicinity of the Pearl River Estuary are expected to strengthen later today and tomorrow morning.
The rain bands associated with Cempaka will bring occasional heavy showers and squalls to the territory today.
The Macau Meteorological and Geophysical Bureau also issued a tropical cyclone alert and has issued the No 3 signal at 2.30pm today.
The NHS said the devices used to monitor blood-oxygen levels at home may give inaccurate readings for people with darker skin.