Air masses and weather maps

In this simplified pattern, much of Eastern Australia is influenced by a warm continental air mass, while a cooler maritime air mass is entering southwest Western Australia. A cold front forms between the two air masses.

As the pressure systems and the cold front move eastward (below), cooler maritime air extends across southern Australia over a few days. As other systems develop to the west of Australia, periods of relatively warmer then cooler conditions are experienced in southern Australia.

Link to animation (15k)
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