China has evacuated hundreds of thousands of people and ordered at least 10 cities to close schools and some businesses as the strongest storm of the year bears down on its southern coast.
Hong Kong has upgraded its typhoon warning to eight - just two levels below the maximum - ahead of the arrival of Super Typhoon Ragasa.
The storm is expected to make landfall in China's Guangdong province on Wednesday, where some 370,000 people have been evacuated so far, as authorities warn of a catastrophic situation.
Ragasa, dubbed the King of Storms by China's meteorological agency, is expected to move towards northern Vietnam in the coming days, potentially affecting millions.
On Tuesday, supermarket shelves in Hong Kong were wiped empty of fresh bread, vegetables, meat, and instant noodles as residents prepared to hunker down. Hong Kong International Airport is set to face significant flight disruptions from 18:00 local time on Tuesday until the next day.
In cities across southern China, shop owners piled sandbags in front of their stores, with residents in low-lying areas particularly worried about tidal surges. Many have also taped up windows in an attempt to fortify against potential damage.
Ragasa has already lashed through the northern Philippines, where it caused one death and massive evacuations. The storm, which can be compared to a Category 5 hurricane, possesses gusts of up to 285km/h (177mph) and has triggered warnings for floods, storm surges, and landslides.
While the extent to which climate change has influenced Ragasa specifically remains unclear, scientists warn that warming oceans may result in more intense tropical storms in the future.
Authorities in Hong Kong have noted the potential for devastation similar to past typhoons, including Mangkhut in 2018, which caused severe damage and economic losses.