THIS year is the 100th anniversary of the typhoon number system in Hong Kong.
Back in 1884, the Hong Kong government used to use different shapes, such as cylinders and spheres, to mark how strong and where a storm was. When the storm was close enough, the government would fire a typhoon gun to warn residents.
In 1917, the government used a number system for the first time to announce the arrival of a storm.
The system went from No 1 to No 7, with No 2 to No 5 saying which direction the storm was coming from. In 1931, the government changed the numbering to No 1 to No 10, with different numbers showing which direction the wind was blowing. Then No 2 to No 4 were cancelled in the late 1930s.
To avoid confusion among the general public about the signals, in 1973 the government reorganised the system into the one we use today. They stopped using different numbers to show direction, and put all gales under No 8, with a note saying which direction the storm is coming from.