Hong Kong's weather forecaster on Saturday said Wutip had weakened into a tropical storm, with the No. 3 warning signal expected to remain in force until at least noon on Sunday.

The Observatory raised the Strong Wind Signal No 3 at 12.20pm, but said the chance of issuing the No. 8 alert was rather low.

Wutip will skirt about 300 kilometres to the northwest of Hong Kong on Sunday morning, according to the forecaster.

"Severe Tropical Storm Wutip has weakened into a tropical storm," it said.

"Locally, strong winds are prevailing over many places, occasionally reaching gale force on high ground in the western part of the territory. The outer rainbands of Wutip are also bringing squally showers to the coast of Guangdong."

It also said local winds would "moderate progressively" on Sunday afternoon with Wutip moving away from Hong Kong and weakening gradually.

"Although Wutip will dissipate gradually on Monday and Tuesday, an active southwesterly airstream will bring heavy showers to the coast of Guangdong," it added.