The Observatory has warned that the weather is expected to be extremely hot over parts of the territory on Thursday and Friday, due to subsiding air associated with a tropical depression.
The tropical depression over the northeastern South China Sea is currently within 800 kilometres of Hong Kong.
It is expected to develop slightly, but will stay about 500 kilometres or more away from the city, moving generally towards the vicinity of Taiwan.
The forecaster said unless the tropical depression strengthens significantly or moves closer to the Pearl River Estuary, the chance of issuing a tropical cyclone warning signal is rather low.
The Observatory reminded the public to pay attention to their health amid the heat.
