Frequency
Tornadoes have occured throughout Australia. Because they are associated with strong thunderstorms, the frequency of tornadoes is closely related to the areas that have lots of thunderstorms, but also occur predominantly in the interior and southern plains where cold air from Anarctica encounters warm air moving southward. It is these contrasting air masses and their common paths of circulation which give rise to both the thunderstorms and the tornadoes. Tornadoes are most common during the spring and summer months. They often occur as swarms associated with cold fronts.
Tornado Damage
Tornado damage is caused by the high wind speed and high difference in atmospheric pressure between the tornado and its surroundings. The rotating winds can knock down weaker structures, and the extremely low pressure inside the tornado generates strong pressure differences between the inside and outside of buildings. This pressure difference causes roofs to be lifted and removed. The high winds pick up smaller objects including small structures, animals, people, cars, and especially mobile homes, and can carry these objects up to several kilometers. The debris picked up by the winds become rapidly moving projectiles that can become lethal when hurled against a human body.
Tornado Prediction and Warning
Tornadoes cannot be predicted with precision. However, when strong thunderstorm activity is detected, a tornado watch is generally issued for all areas that may fall in the path of the thunderstorm. Doppler radar can detect rotating motion within a thunderstorm and when this is detected, or a tornado is actually observed, a tornado warning is issued for all areas that may fall in the path of the thunderstorm.
