It left more than 7,350 people dead or missing across the central Philippines in November 2013.
The category 5 "super" typhoon hit the northern end of the Philippine island of Luzon early on Saturday morning, with the high winds ripping the roofs off houses and pulling down trees and electricity pylons, and the rains causing fatal landslides and flooding.
China and the Philippines agreed to postpone a visit by Chinese Foreign Minister Wang Yi that was to start Sunday due to the onslaught, which caused almost 150 flights, a third of them global, to be canceled and halted sea travel.
"Hong Kong as of the forecast now will be on the right quadrant of the storm with the greatest impacts from wind, rain and storm surge along that coast line", he said. He said he remembers one typhoon from his childhood.
Filipino villagers lift electric wires in the typhoon-hit town of Lal-lo, Cagayan province, Philippines, Sept. 15, 2018.
"It was not so severe as we expected it to be because earlier it was noted it would also be strong", said President Rodrigo Duterte, following an aerial survey of some affected areas.
The dead were six people killed in landslides, a girl who drowned and a security guard crushed by a falling wall.
Mangkhut, the Thai name for Southeast Asia's mangosteen fruit, skirted 100 km (62 miles) south of Hong Kong and veered west towards the coast of Guangdong and the gaming centre of Macau.
There have so far been no immediate reports of major damages or casualties in the region, where a massive evacuation from high-risk areas has been under way for the last two days. Tolentino and other officials advised them not to return home until the lingering danger had passed.
There are immediate deaths reported but Defense Secretary Delfin Lorenzana says officials in northeastern Cagayan province where the typhoon slammed ashore before dawn are verifying the drownings of two children.
ASSOCIATED PRESS A convenience store is taped in preparation for approaching Typhoon Mangkhut in Hong Kong on Saturday
Before the storm made landfall, Civil Defense used that knowledge to pre-position hundreds of thousands of food packs. Tens of thousands more have been evacuated from China's Guangdong province, CNN reported.
Some roads were waist-deep in water with parts of the city cut off by floods and fallen trees on Sunday afternoon as the rains continued.
Residents walk on flooded streets as typhoon Mangkhut batters their city on September 15 in Tuguegarao, Philippines.
Many stores and houses were damaged but most residents remained indoors as occasional gusts sent small pieces of tin sheets and other debris flying dangerously.
The Tuguegarao airport terminal also was damaged, its roof and glass windows shattered by strong winds.
Farms across Luzon, which produces a large portion of the nation's rice and corn, were sitting under muddy floodwaters, their crops ruined just a month before harvest.
Gusty winds with occasional moderate to heavy rains are expected over Visayas, while scattered light to moderate to at times heavy rains over Palawan, Zamboanga Peninsula, Northern Mindanao and CARAGA.
More than 4 million people were declared at risk from the storm, and around 87,000 evacuated, with 105,000 are staying in temporary shelters, according to Reuters. It now packed sustained winds of 155 kilometers (96 miles) per hour and gusts of up to 190 kph (118 mph).
Hong Kong authorities on Sunday morning raised its hurricane alert level for the city to a signal 10 - the highest level - and told residents to brace for winds of up to 120 miles per hour in some parts of the city.