The Hong Kong Observatory said it will consider issuing the Gale or Storm signal No 8 in the wee hours of Sunday.

Severe tropical storm Wipha is forecast to move across the northeastern part of the South China sea and edge closer to the coast of Guangdong.

At a press briefing on Saturday, acting senior scientific officer Shum Chi-tai said strong winds will start picking up later on Saturday.

"According to the present forecast, Wipha will continue to intensify and move towards the vicinity of the Pearl River Estuary today, with its outer rain bands and associated strong winds affecting the coastal areas of Guangdong gradually," he said.

"Local winds will strengthen later today."

There will also be more showers gradually with squally thunderstorms, according to the observatory.

Flooding may occur in low-lying coastal areas tomorrow morning due to the influence of storm surges.

Shum was speaking as Secretary for Home Affairs Alice Mak said her bureau had already started preparatory and prevention works ahead of the typhoon to minimise the impact of Wipha on the public.

Speaking on Saturday, she said the 18 district offices, district councillors, village representatives and care team members had started on the work, particularly in outlying and low-lying areas.

"Village representatives have contacted villagers in outlying areas and helped them prepare ahead of the storm," Mak said.

"In some of the areas that are more easily flooded, sandbags have been put in place to prevent flooding," Mak said.

"As for low-lying areas, we have closed flood gates at locations where the Drainage Services Departments have installed them," she added.

Mak also said community centres and halls will be open when the No 8 is in force for use as temporary shelters.

Staff will also be deployed to assist people in need, she said.