Rainfall deficiencies

Issued 7 October 2015

A dry September sees deficiencies persist or slightly increase

September rainfall was below average for most of Australia. Below-average rainfall was observed in Tasmania and a broad swathe of the mainland extending across agricultural South Australia, nearly all of Victoria, much of New South Wales west of the ranges, through southern and western Queensland, the majority of the Northern Territory, and most of Western Australia. September was amongst the ten driest Septembers on record for Victoria, Tasmania and Western Australia.

Following a generally very dry month, deficiencies have increased slightly in both severity and extent at all monitored timescales when compared to the last Drought Statement. Increases were most notable in southwest Western Australia at the shorter 5-month and 15-month timescales (May to September 2015, and July 2014 to September 2015 respectively), while increases in eastern Australia in Queensland, Victoria and adjacent southeast South Australia were generally similar across all three monitored periods (including the 36-month October 2012 to September 2015 period).

Serious or severe rainfall deficiencies have been observed in parts of southeast Australia for various medium-term periods since late 2013, and for longer-term deficiencies for various periods to around 2 years duration. For eastern Australia more generally, rainfall has been very much below average for large areas for periods of about 3 years' duration, in Queensland largely as a result of poor wet-season rainfall in successive years. Long-term deficiencies also exist in eastern Australia over the 17 years since 1998.

The southern wet season, which spans April to November, continues to track below average rainfall for the season so far in central to western Victoria, southeastern South Australia, Tasmania, and across most of the South West Land Division in Western Australia.

5-month rainfall deficiencies

Below-average September rain has seen rainfall deficiencies increase in southwest Western Australia, parts of southeast South Australia and western to central Victoria, as well as in parts of coastal eastern Tasmania at the 5-month timescale (May to September 2015). Severe deficiencies (lowest 5% of historical records for similar periods) persist over most of southwest Western Australia (the area southwest of a line between Jurien Bay and Bremer Bay).

Pockets of serious rainfall deficiencies (lowest 10% of historical records) are in place in far southeastern South Australia and an adjacent part of the Wimmera in Victoria, central Victoria, and eastern Tasmania. Much of Victoria and southeastern South Australia have received below-average rainfall for the five-month period and for the cool season to date.

Deficiencies have also increased in some parts of northern Australia, although September is typically the last month of the northern dry season. Rainfall is typically low over most of northern Australia between May and September. Areas of deficiencies persist in parts of the north of Western Australia and adjacent to Queensland's East Central Coast.

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15-month rainfall deficiencies

For the 15 months July 2014 to September 2015, deficiencies have generally increased in extent or severity in all affected regions.

Severe or serious deficiencies (lowest 5% or lowest 10% of historical records) persist in an area extending from northwestern South Australia, along the coast of South Australia, and across most of Victoria except Gippsland and parts of the Alps. Rainfall for the period remains lowest-on-record for an area spanning southeastern South Australia and adjacent parts of western Victoria. Serious or severe deficiencies also persist in western and northern Tasmania. Severe deficiencies (lowest 5% of historical records) affect 47% of Victoria—a value that has not been exceeded for a 15-month July–September period since 1944–45.

Much of southeastern Australia has seen below-average April–November rainfall during three of the last four years, with monthly rainfall also below average from August last year for much of this region (apart from well-above-average January rainfall, and above-average March and May rainfall in Tasmania).

Deficiencies also persist along the west coast of southwest Western Australia, and in areas of northern Queensland extending across the southern and central Cape York Peninsula, roughly from Kowanyama to Townsville, along the southern coast of the Gulf of Carpentaria, and in an area of inland central Queensland near Longreach.

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36-month rainfall deficiencies

At the 36-month timescale (October 2012 to September 2015), rainfall deficiencies have increased slightly in extent or severity in all affected regions.

Severe or serious deficiencies (lowest 5% or lowest 10% of historical records) persist in Queensland, extending from the base of the Cape York Peninsula, through central Queensland into parts of central southern Queensland and northern New South Wales to the west of the Great Dividing Range. Deficiencies also persist in an area spanning southeast South Australia and much of western to central Victoria, pockets along the west and east coast of Tasmania, and parts of the central South West Land Division in Western Australia along a line roughly from Jurien Bay to Albany.

Deficiencies also persist at a range of even longer timescales, with most of eastern Australia having received below-average rainfall following the conclusion of the 2010–12 La Niña events.

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Black and white | High resolution colour

Soil moisture

Soil moisture in the upper layer for the week ending 27 September had decreased across nearly all of Australia compared to the week ending 30 August.

Upper layer soil moisture was below to very much below average in the west of Western Australia, across most of southern Australia, nearly all of Tasmania, and in much of New South Wales and large parts of Queensland. Upper layer soil moisture was above average in some areas along the coast between East Gippsland in Victoria and southeastern Queensland.

Lower-layer soil moisture for the week ending 27 September was generally similar to that for the week ending 30 August, with slight decreases in much of southern Australia and parts of inland Queensland.

Lower-layer soil moisture was above average for a large area of Western Australia between the northwest and southeast, the central Northern Territory, far eastern Victoria and southeastern New South Wales, parts of western New South Wales, and parts of South Australia but not the southeast. Soil moisture was below average in western parts of the South West Land Division in Western Australia, and also for areas of coastal northern Queensland, around the Gulf coast, parts of the Top End, some areas between central Queensland and northern New South Wales, much of central to western Victoria and southeastern South Australia, and parts of eastern Tasmania.

Further information

(03) 9669 4057


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

The 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.

It is generally difficult to compare one drought to another, since each drought differs in the seasonality, location, spatial extent and duration of the associated rainfall deficiencies. Additionally, each drought is accompanied by varying temperatures and soil moisture deficits.

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.


Lowest on record - lowest in the historical analysis, which runs from 1900.
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.


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'