I'm quite impressed how small, and how potent, the cyclones are that develop along the eastern shore of Australia. On some days (like maybe June 3rd), the vorticity helps contribute to phenomena like waterspouts. The area is just east of the Great Dividing Range and the New England Plateaus, and thus subject to lee cyclogenesis due to the conservation of potential vorticity:
Since f is approximately constant, the flow must assume negative vorticity or anticyclonic turning, i.e. counterclockwise turning in the southern hemisphere. By the same token, on the lee side, the expansion of the isentropic layer demands positive vorticity or clockwise turning. A ridge over mountains and a trough in its lee are often observed. Below the upstream side of the trough a low may form and intensify at the surface (Note 12.L). This process is called lee cyclogenesis and explains why midlatitude cyclones form in the lee of mountain ranges, e.g. to the east of New Zealand and southern South America (Fig 6). These lows or troughs are responsible for most of the rainfall along the coast.
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