The Hong Kong Observatory has issued the No 1 warning signal as Typhoon Man-yi approaches the city.
The forecaster issued the signal at 6.40am on Monday.
The typhoon made landfall in the Philippines on Sunday and is expected to move northwest or west-northwest at about 25km/h (15.5mph) and enter the central and northern parts of the South China Sea.
The Observatory also warned temperatures were likely to gradually fall in the next couple of days.
“There will be occasional rain on Tuesday and Wednesday. Temperatures will fall progressively, with the minimum temperature falling to 18 degrees Celsius or below,” it said.
The forecaster added that there would be a spring tide in the next couple of days, and under the combined effect of the northeast monsoon and Man-yi, minor flooding could occur in individual low-lying areas.
