1.9 The anatomy of a Typhoon

A tropical cyclone is a rotating mass of warm humid air with the lowest pressure near its centre. Most tropical cyclones form between Latitudes 5 and 20 on both sides of the Equator.

With maximum winds exceeding 118 kilometers per hour, this phenomenon is called a typhoon in the western Pacific and the China Seas.

Hong Kong is most likely to be affected by typhoons in September, although typhoons of varyhing strength can occur at any time between May and November. On average, 24 typhoons develop each year over the western Pacific and the South China Sea.

Of these about six may come within 800 kilometers of Hong Kong. An average of one typhoon a years come close enough to bring severe winds, intense rainfall and tumultuous seas.

Credit : History Museum of HK.