Hong Kong on Wednesday raised a tropical cyclone signal 8, its third highest level, as schools and financial markets closed and office workers left work early to get home before the storm.
The Hong Kong observatory said Typhoon Wipha was edging closer to China's coast in the southwestern part of Guangdong province, skirting about 300 km (186 miles) west of the city.
"The gale or storm signal, No. 8 is expected to remain in force for most of rest of today," the observatory said.
The highest warning signal is 10.
The approaching storm brought heavy rain, strong wind and stormy seas. The education bureau closed schools for the day, and authorities urged office workers to head home.
The city's financial markets shut early and would not reopen on Thursday if the typhoon signal remains at 8 or higher at 9 a.m. (0100 GMT).
Trading will be suspended for the whole day if the storm signal is still at 8 or higher at noon on Thursday.
Neighbouring Macau is also expected to be affected.