Rainfall deficiencies

Australia is a large continent containing many different climate zones, from wet tropics in the north, arid and semi-arid conditions in the interior, and alpine climates in the south-east. Each climate zone is influenced by very different large-scale, predominant weather and climate patterns. For this reason, at any time different parts of the Australian continent can be affected by very different climate extremes. An example of this occurred in 2010, where southwest Western Australia experienced its driest year on record, in contrast to the rest of Australia, which received above-average to very-much-above-average rainfall.

Use our Drought Statement, rainfall maps and reports to watch for areas with significant long and short-term rainfall deficiencies.

Issued on 5 September 2014 by the National Climate Centre

Rainfall deficiencies ease in central eastern Australia, worsen in the south and west

August rainfall was well-below-average across southern Australia with unusually persistent and strong highs, while two significant low pressure systems resulted in well-above average rainfall over much of inland New South Wales and Queensland and almost the entire east coast strip, although rainfall over areas experiencing deficiencies was not sufficient to cause dramatic change.

Deficiencies at the shorter timescale have eased somewhat along the east coast, although Western Australia’s sixth-driest August on record caused an increase in the number of locations experiencing deficiencies along the western and southern coast. Deficiencies at the longer timescale have also increased in central and western Victoria and remain similar elsewhere.



Though August rainfall was above average over coastal eastern Australia, northern New South Wales and much of Queensland, these falls are above average for the dry season — the actual totals were low away from the coast and have not had a significant impact on long-term rainfall deficiencies. Rainfall deficiencies for the 9 months from December 2013 to August 2014 have decreased in extent and severity over southeastern Queensland and northeastern New South Wales, while dry conditions have seen these increase along the southwest and southern coasts of Western Australia. Serious and severe deficiencies (lowest 10% and 5% of records) are present in a large area of northeastern New South Wales and greater southeastern Queensland as well as isolated pockets in other parts of Queensland, small areas along coastal parts of Western Australia, along the west coast south of around Carnarvon and the south coast to just east of Esperance.

Much of northeastern New South Wales and greater southeastern Queensland also shows serious or severe deficiencies for the 12 months from September 2013 to August 2014.



Rainfall deficiencies for the 23-month (October 2012 to August 2014) period have remained largely unchanged across Australia when compared to the 22-month period ending July. The only area where rainfall deficiencies have slightly changed is in western Victoria where deficiencies have increased in spatial extent and severity.

Serious and severe deficiencies (lowest 10% and 5% of records) remain in an area spanning much of Queensland away from the eastern coast and also in smaller areas in adjacent parts of the Northern Territory and South Australia, and in an area inland of the Great Dividing Range extending from southern Queensland into northern New South Wales. The area of deficiencies in inland western Victoria has again increased in size compared to the previous Drought Statement, in line with drier conditions which have prevailed in the region in the months since the wetter-than-average April.

More generally, rainfall for the 23-month period ending August 2014 has continued to be below average over the eastern mainland and parts of Tasmania. There are large areas of Australia which have seen rainfall which is below-average but above the lowest 10% of records, highlighting that the spatial extent of below-average rainfall in the southwest and eastern parts of Australia is widespread on this timescale.



Upper layer weekly soil moisture for the week ending 31 August was below to very much below average across much of Victoria and the mainland south coast, Tasmania and western parts of Western Australia. Soil moisture was above average along the east coast of New South Wales and southern Queensland, from inland central New South Wales through to central northern Queensland, and also along the coastal Pilbara and Kimberley in Western Australia. The increase in upper layer soil moisture in central New South Wales into Queensland and a decrease in Victoria and western parts of Western Australia is largely representative of August rainfall patterns.

Lower layer weekly soil moisture for the week ending 31 August remains similar to last month, with a slight increase across the Cape York Peninsula. Soil moisture was below average across parts of inland and southeastern Queensland, northeastern New South Wales, along the west coast of Western Australia extending from the Pilbara to the Central Wheat Belt and in the central Top End. Soil moisture is above average across the central Cape York Peninsula, central Northern Territory and much of the western half of Western Australia as well as pockets of the coastal Top End. Soil moisture is also above average along the south coast from the Nullarbor Plain through South Australia and western Victoria with slightly above-average soil moisture in far eastern Victoria, eastern Tasmania and scattered patches of the mainland southeast.



Click on the map for full resolution.

Click on the map for full resolution.
Black and white version

Click on the map for full resolution.

Click on the map for full resolution.
Black and white version

A mob of sheep raises dust north of Dubbo, New South Wales, during drought. Photo by Department of Foreign Affairs and Trade

Definitions

Further information

Media
(03) 9669 4057
Enquiries

Get email alerts for the Drought Statement


Product Code IDCKGD0AR0

This section displays rainfall maps. Current drought status is described in the previous section. For historical drought status statements, go to archive of drought statements

These maps are also available from Maps - recent conditions

Weekly rainfall updates

Current map, small viewThe Weekly Rainfall Update describes rainfall over the previous week. It includes a map and a summary table of the highest weekly totals. A discussion of the impact of recent rains on rainfall deficiencies is also presented.

Rainfall and temperature outlooks

Current map, small viewRainfall and temperature outlooks outline likely conditions over three-month periods. Outlooks are available for single months, three months, and for any location in Australia. Formats include text summaries, maps, graphs and video.
Rainfall and temperature outlooks: Outlooks
Previous outlooks: Archive of outlooks Archive of outlook maps

Seasonal streamflow forecasts

Australian streamflows are among the most variable in the world. Seasonal streamflow forecasts extends water management decision making capability. Forecasts are issued monthly.

Climate statements archive

The archive includes previous monthly, seasonal and annual climate summaries for nation-wide, state/territory and capital city conditions.

Maps of recent conditions

CSIRO water balance maps

Small image of water balance mapCSIRO (AWAP) Water balance maps include maps of soil moisture and water fluxes contributing to changes in soil moisture (rainfall, transpiration, soil evaporation, surface runoff and deep drainage).

What is drought?

Drought is a prolonged, abnormally dry period when the amount of available water is insufficient to meet our normal use. Drought is not simply low rainfall; if it was, much of inland Australia would be in almost perpetual drought. Because people use water in so many different ways, there is no universal definition of drought. Meteorologists monitor the extent and severity of drought in terms of rainfall deficiencies. Agriculturalists rate the impact on primary industries, hydrologists compare ground water levels, and sociologists define it by social expectations and perceptions.

Rainfall averages, variability and trends

Median rainfall map, links to climate average maps An area experiences a rainfall deficit when the total rain received is less than the average rainfall for that period.

Definitions

Lowest on record - lowest since at least 1900 when the data analysed begin.
Severe deficiency - rainfalls in the lowest 5% of historical totals.
Serious deficiency - rainfalls in the lowest 10% of historical totals, but not in the lowest 5%.

Very much below average - rainfalls in the lowest 10% of historical totals.
Below average - rainfalls in the lowest 30% of historical totals, but not in the lowest 10%.
Average - rainfalls in the middle 40% of historical totals.
Above average - rainfalls in the highest 30% of historical totals, but not in the highest 10%.
Very much above average - rainfalls in the highest 10% of historical totals.

Acknowledgements

Front page photo, provided by Department of Foreign Affairs and Trade: 'A mob of sheep raises dust north of Dubbo, New South Wales, during drought'