Cyclones

Tropical Cyclones are dangerous because they produce destructive winds, heavy rainfall with flooding and damaging storm surges that can cause inundation of low-lying coastal areas.

A Tropical Cyclone is a low pressure weather system that forms over warm tropical waters and can produce wind gusts of up to 280 kilometres per hour. These strong winds can cause injury, loss of life, major structure damage to communities, disruption of utility and telecommunications services and turn debris into dangerous missiles.

In Western Australia (WA) cyclone season commences in November and continues through to April.

During this time coastal regions of WA are at risk of being impacted by cyclones. Heavy rainfall associated with the passage of a tropical cyclone can produce extensive flooding. This can cause further damage and death by drowning. The heavy rain can persist as the cyclone moves inland and decays, hence flooding due to a decayed cyclone can occur a long way from the tropical coast as the remains of a cyclone move into central and southern parts of the continent.

                                                                       Storm surge and tides

Potentially, the most destructive phenomenon associated with tropical cyclones that make landfall is the storm surge. Storm surge is a raised dome of water about 60 to 80 km across and typically about 2 to 5 m higher than the normal tide level. If the surge occurs at the same time as a high tide then the area inundated can be quite extensive, particularly along low-lying coastlines