Isohyets

This Isohyet map shows the rainfall in Tasmania. As you can see from the map there is little rainfall in the eastern part of Tasmania but the western part of it averages nearly 3,000 millimeters of rainfall annually. The airflow from the Southern Ocean is moisture-laden. When it rises over the western, central, and southern highlands it releases its moisture as rain. As the air flow reaches the eastern parts it has already reduced most of its moisture, and the chance of rain is reduced dramatically. As you can see there is a drastic difference in average cloudiness and rainfall.

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