The Hong Kong Observatory will issue the gale or storm signal No. 8 at 2:20 pm on Tuesday, as Super Typhoon Ragasa continued to move closer.

At 10 am, the super typhoon was estimated to be about 460 kilometers east-southeast of Hong Kong and was forecast to move west-northwest at about 22 km per hour across the northern part of the South China Sea, gradually edging closer to the coast of Guangdong, the HKO said in a bulletin.

It will be mainly cloudy with sunny intervals during the day on Tuesday but the weather was expected to worsen later with squally showers and thunderstorms.

“Under the influence of its (Ragasa’s) extensive circulation, the weather over the coastal areas (in Guangdong) will deteriorate rapidly with winds strengthening significantly later today (Tuesday),” the bulletin reads.

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A “pre-No 8 special announcement” will be made about two hours before issuing the signal No. 8 to replace the strong wind signal No 3, which has been in force since 9:40 pm on Monday.

The forecaster said Ragasa will maintain super typhoon intensity and be closest to the vicinity of the Pearl River Estuary on Wednesday morning.

Depending on the distance between Ragasa and Hong Kong and the change in local wind conditions, the observatory said it will assess the need of issuing higher warning signals in the latter part of Tuesday night to early Wednesday.

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Reiterating its warning that the weather will be persistently adverse on Wednesday, the HKO stressed that gale to storm force winds will prevail, and winds may reach hurricane force offshore and on high ground, with frequent heavy squally showers and thunderstorms.

Meanwhile, seas will be very high with swells and there will be a rise in water level of about 2 meters over coastal areas of Hong Kong on Wednesday morning under the influence of significant storm surge, according to the weather forecaster, adding that the maximum water level can generally reach around 3.5 to 4 m above chart datum.

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With the departure of Ragasa, winds were expected to weaken gradually but showers will still be heavy at first on Thursday. The weather will improve in the latter part of this week.