Sources of Tropical Cyclones

1. Landfall from the east
In this scenario a tropical cyclone generated in the Coral Sea moves southwards and crosses the NSW coast as a cyclone. This scenario can result in destructive winds, large swells, storm surge and torrential rain. Examples include Tropical Cyclone 137 in 1954 and Tropical Cyclone Nancy in 1990.

2. Overland from Queensland
Cyclones that cross the coast in the Gulf of Carpenteria and travel overland through Queensland into New South Wales. These can bring very heavy rain and destructive winds. Examples include Tropical Cyclone Audrey in 1964 and Tropical Cyclone 119 in 1950.

3. By generating large swells
As cyclones track offshore past the New South Wales coast they can generate very large swells that can cause beach erosion. Examples include Tropical Cyclone Pam in 1974 and Tropical Cyclone Yali in 1998.

It should be remembered that in addition to affecting the New South Wales coastline, tropical cyclones can also affect the NSW Territory of Lord Howe Island. Examples include Tropical Cyclone Pam in 1974 and Tropical Cyclone Kirsty in 1973.

Tropical cyclones cause damage in a number of ways - these include:

1. River flooding     Very heavy rainfall associated with tropical cyclones can result in both localised flash flooding as well as riverine flooding. For example, major flooding in the Tweed and Lismore areas in 1954 and 1974 were the result of tropical cyclones. Further information on flooding including safety and preparedness information is available from the FloodSafe section of the SES website.

2. Storm surge and coastal erosion     Tropical cyclones can raise sea levels by tens of centimetres to several metres. This can result in the flooding of low lying coastal areas and combined with large waves can cause significant erosion of beaches and sand dunes that could threaten coastal property. Further information on coastal erosion is available from the Coastal Erosion and Inundation section of the SES website.

3. Damage from Wind     Wind is a defining feature of tropical cyclones, and in severe cyclones wind gusts are highly destructive.

Further information on Tropical Cyclones

Bureau of Meteorology - warnings, background and reference information as well as information on safety and preparedness.

Emergency Management Australia - background and reference information as well as information on safety and preparedness.