The Hong Kong Observatory is considering issuing the No. 1 typhoon warning signal on Wednesday morning with a tropical cyclone edging closer to the city.

A broad area of low pressure over the central part of the South China Sea is consolidating at a distance of around 800 kilometers from Hong Kong and would gradually develop into a tropical depression on Tuesday afternoon or Wednesday morning, the forecaster said in a 08:20 am bulletin on Tuesday.

The area of low pressure will gradually develop into a tropical depression between Tuesday afternoon and Wednesday morning, it said.

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“The observatory will issue the Standby Signal, No. 1 tomorrow (Wednesday) morning at the earliest,” reads the bulletin.

The forecaster warned that as the tropical cyclone edges closer, the weather will be windy with occasional squally showers in the latter part of this week, accompanied by swells.

On Tuesday, it will be very hot during the day, apart from isolated showers, it said, adding that there will be light to moderate east to northeasterlies winds.

The tropical cyclone is expected to move in the general direction of Hainan Island and the vicinity of the coast of western Guangdong in the middle and latter parts of this week, according to the HKO.

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“Depending on its distance from Hong Kong and its rate of development, the observatory will assess the need of issuing a higher tropical cyclone warning signal on Thursday,” the bulletin added.

Precautions against heat stroke

With a very hot weather warning in force, the Centre for Health Protection of the Department of Health reminded members of the public, particularly those undertaking outdoor activities, on Tuesday to take necessary measures against heat stroke and sunburn.

The public should carry and drink plenty of water to prevent dehydration while engaging in outdoor activities, said a CHP spokesman.

“Those engaged in strenuous outdoor activities should avoid beverages containing caffeine, such as coffee and tea, as well as alcohol, as they speed up water loss through the urinary system," added the spokesman.

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Infants and children, the elderly, pregnant women, those with chronic illnesses such as heart disease or high blood pressure, outdoor and manual workers, and individuals who are overweight are more vulnerable to heat stroke and should pay special attention, the spokesman added.