About the rainfall timeseries graphs
Analyses available
Australian and regional rainfall timeseries are available from 1900 for annual, financial year, seasonal and monthly rainfall, as well as for the southern (April–November) and northern (October–April) wet seasons. Prior to 1900 Australia's rainfall network was too sparse for reliable continental scale analyses.
Note that even though the rainfall timeseries are updated each month, values for recent months should be considered preliminary as it can take several months to fully enter and quality-control all available rainfall data into the database. A climatology (average rainfall) is calculated over a 30 year period; usually 1961–1990 for all periods except summer, northern wet season and the financial year. For these periods, the climatology starts during first month in 1961 and ends in the last month in 1991. For instance, the climatology period for summer ranges from December 1961 to February 1991.
Area average rainfall timeseries are provided for each of the six Australian States and the Northern Territory, all of Australia, and six climatologically distinct regions; northern Australia (north of 26°S), southern Australia (south of 26°S), southwestern Australia (southwest of the line joining 30°S, 115°E and 35°S,120°E), southeastern Australia (south of 33°S, east of 135°E), eastern Australia (Queensland, New South Wales, Victoria and Tasmania), and the Murray–Darling catchment. Values calculated for New South Wales include the Australian Capital Territory. The graphs are plotted with a consistent range for the appropriate timeseries.
Timeseries are determined for each Australian State, the Northern Territory and the six regions shown above
Data used
The Bureau of Meteorology has upgraded its monthly gridded rainfall analysis. The enhanced analysis known as Australian Gridded Climate Data (AGCD) employs state-of-the-art statistical modelling and improvements in scientific techniques, to provide the Australian community with a more accurate representation of monthly, seasonal and annual rainfall in their region.
The Bureau has a vast network of manually-read and automated rain gauges across Australia but it's not possible to place this type of infrastructure every few kilometres. While these rain gauges provide rainfall data at point locations, gridded analysis allows the Bureau to provide an accurate estimate of rainfall in much wider areas.
The enhanced analysis has been applied to the Bureau's historical rainfall data which is crucial to ensuring consistency between past and future monthly gridded rainfall data.
Further details about the gridded rainfall analysis
Please note that any use of these data should be acknowledged to the Bureau of Meteorology. Apart from the purposes of study, research, criticism and review, no part of these data may be reproduced, or redistributed for any commercial purposes, or distributed to a third party for such purpose, without written permission from the Director of Meteorology.
The actual area-averaged data values used to produce each graph are available via the "Raw dataset" link. The format for these data is:
<start year><start month><end year><end month> <mean rainfall value (mm)>
The "Sorted dataset" link provides the timeseries as a chronologically sorted list in order to place recent values in historical context.
Rainfall network
A representation of the spatial and temporal coverage of available station data used in the analysis is shown in the figure below. Counts are made for the number of years of which at least one station of monthly data occurs within a 0.25 x 0.25 degree grid cell (approximately 25 km x 25 km). The clipping of the relatively course grid to the coastline may result in some grid cells not fully resolving potential site coverage.
The full source station rainfall data from Bureau sites can be accessed via the Climate Data Online page
Representative locations of rainfall stations included in spatial averages
Further information
More information on the methods and science behind the AGCD can be found in the peer-reviewed technical report
