Hong Kong is a city well prepared for typhoons, with a detailed warning system that alerts residents to the severity of any approaching storm so that they know how — and how quickly — to respond.

But when Typhoon Mangkhut battered the city with 100 miles-per-hour wind gusts on Sunday, its intensity took many Hong Kongers by surprise.

The local news media said the Hong Kong Observatory had labeled Mangkhut the most intense storm to hit the city, a major financial hub, since records began in 1946.