The observatory issued Hurricane Signal No 10 at 8.15pm on Friday as the eyewall of Super Typhoon Saola passes through Hong Kong.
While it’s not a direct hit, the territory will be subjected to the wall of wind surrounding the storm centre – where sustained winds are thought to be moving at speeds of up to 210 kilometres per hour.
The observatory said the storm is now posing a ‘high threat’ to Hong Kong.
“Hurricane force winds are affecting the eastern part of Hong Kong,” it said.
“According to the present forecast track, Saola will skirt around 40 kilometres to the south of the Hong Kong Observatory in the next few hours. The Hurricane Signal, No. 10 is expected to remain in force for some time”, it added.
Members of the public are also advised to be prepared for a change in wind direction, as northerly winds will shift gradually to east to southeasterlies, and expose previously sheltered areas to the full force of the storm.
“You are advised to remain where you are if protected and be prepared for destructive winds,” the forecaster warned.
The Increasing Gale or Storm Signal No 9 was issued less than two hours prior to the T10.
The last time the top storm warning was issued was in September 2018 when Super Typhoon Mangkhut passed Hong Kong. That storm signal was in force for ten hours.