Packing maximum sustained winds of 234km/h near its centre, Yagi registers as the world's second-most powerful tropical cyclone of 2024, after the category five Atlantic hurricane Beryl, and the most severe in the Pacific basin of the year.
After more than doubling in strength since killing 16 people in the northern Philippines this week, Yagi slammed into the city of Wenchang on Hainan island.
Typhoon Yagi killed 16 people when it hit the northern Philippines this week. (AP PHOTO)
The typhoon on Friday shut schools, businesses and transport links in Hong Kong, Macau, Hainan and Guandong as well as airports in Vietnam, which it is predicted to hit, along with Laos, at the weekend.
Vietnam's Civil Aviation Authority said four airports in the north, including Hanoi's Noi Bai International, would be closed on Saturday due to the storm.
In the financial hub of Hong Kong, the stock exchange was shuttered while schools remained closed on Friday as a precautionary measure.
Hong Kong's airport authority said operations had largely returned to normal after 50 flights were cancelled on Thursday, and the city of more than seven million people also lowered its typhoon warning by a notch after midday, with winds expected to weaken gradually as Yagi moves away, allowing businesses to reopen.
The world's longest sea crossing, the main bridge linking Hong Kong with Macau and Zhuhai in Guangdong, also reopened on Friday afternoon after being shut since Thursday.
However, intense rainbands associated with Yagi will still bring heavy squally showers to the territory.
Yagi, which strengthened into a super typhoon on Wednesday night, is the most severe storm to land in Hainan since 2014, when Typhoon Rammasun slammed into the island province as a category five tropical cyclone.
Streets were deserted as people stayed indoors in Hainan's capital, Haikou, before Typhoon Yagi. (AP PHOTO)
Rammasun killed 88 people in Hainan, Guangdong, Guangxi and Yunnan and caused economic losses of more than 44 billion yuan ($6.25 billion).
Formed over the warm seas east of the Philippines and following a similar path to Rammasun, Yagi arrived in China as a category four typhoon, ushering in winds strong enough to overturn vehicles, uproot trees and severely damage roads, bridges and buildings.
In Hainan's capital Haikou, streets were deserted as people stayed indoors, photographs on social media showed.
Its landfall in Hainan is rare, as most typhoons landing on the duty-free island are classified as weak.
Typhoons are becoming stronger, fuelled by warmer oceans, amid climate change, scientists say.
Last week, Typhoon Shanshan slammed into southwestern Japan, the strongest storm to hit the country in decades.
