Verification of Australian monthly district rainfall totals using high resolution gridded analyses

The use of district rainfall totals for the description of Australian rainfall on monthly and longer time-scales has been investigated using a gridded rainfall dataset generated using an objective analysis technique. It has been verified that the operational district totals, generated within the Bureau of Meteorology for rainfall monitoring and prediction purposes, provide a reasonable indication of rainfall on the whole, both in the mean and in individual months. Some deficiencies have been found in the district totals in certain parts of the country, most notably in the subtropical parts of Western Australia, southern half of the Northern Territory, tropical Queensland, and western Tasmania. In each of these areas districts encompass geographical regions with large spatial variation in rainfall, and the distribution of stations available for the calculation of district average rainfall is not sufficient. The appropriateness of the district boundaries and the variability of rainfall within districts is also investigated.