Drought
Rainfall deficiencies and water availability

Below average rainfall in south-eastern Australia

April rainfall was below average to very much below average (in the lowest 10% ofAprils since 1900) for:

• Tasmania
• eastern South Australia
• most of Victoria
• across the south-eastern ranges and inland slopes, and in the western corners of New South Wales
• parts of the west coast and the interior of Western Australia.

It was Tasmania's driest April since 2015 with area-averaged rainfall 51% below the 1961–1990 average.

April rainfall was above to very much above average (in the highest 10% of all Aprils since 1900) for southern parts of Western Australia away from the west coast.

Further details: Monthly climate summaries, Latest National climate summary

Persistent low rainfall in recent months

Persistent low rainfall conditions have affected much of southern Australia in recent seasons. Since early 2023, rainfall deficiencies (rainfall totals in the lowest 5% since 1900) have developed in Western Australia, South Australia, Victoria and Tasmania. Rainfall deficiencies have been especially significant in regions with western-facing coastlines, including the south-east of South Australia. During this time, soil moisture content, runoff, streamflow and water storage levels have all decreased across much of southern Australia.

For Tasmania, January to April rainfall was 48% below the 1961–1990 average, the driest start to the year on record since the national dataset began in 1900.

Maps: Recent and historical rainfall maps

A 2025 year-to-date rainfall deficiency period has been added to the Drought Statement to monitor recent deficiency development, in addition to the 15-month and 25-month rainfall deficiency monitoring periods.

Cool season rainfall

Southern Australia receives most of its annual rainfall during the cooler months, between April and October. For the region, it means that:

• it is the main growing season for many crops, pasture and forests
• there is typically increased soil moisture content and runoff
• there is typically increased streamflow, leading to increases in water storage levels.

The first significant rainfall in the cool season, in the autumn, typically marks the start of crop and pasture growth in the south. This rainfall is commonly called the 'Autumn Break'. Agricultural requirements for autumn rainfall differ from region to region, but typically this requires rainfall over a number of days to provide soaking moisture that reaches plant roots.

During March and April, large areas of the south-west of Western Australia, eastern Victoria, coastal, northern and parts of central and southern New South Wales, and north-eastern Tasmania received at least 25 mm over 3 days or 30 mm over 7 days. However, these thresholds have not yet been reached in 2025 for almost all of South Australia, and western and central Victoria.

Recent weather patterns

So far in 2025, weather patterns across southern Australia have been dominated by slow-moving high pressure systems. This is a continuation of weather patterns seen throughout much of 2024. These slow moving high pressure systems have resulted in persistent warm and dry conditions, with fewer outbreaks of cold air or rain-bearing weather systems.

More broadly, the Southern Annual Mode (SAM) has been positive for most of 2025. This has resulted in high pressure systems being further south than usual for this time of year across the southern hemisphere.

Climate change

State of the Climate 2024 has indicated that there has been a shift towards drier conditions across southern Australia, especially for the cool season months from April to October. While some areas can have above average rainfall in some seasons, for southern Australia as a whole April to October rainfall has been below the historical (1961–1990) average in 24 the last 30 years since 1994.

The declining trend in rainfall is associated with a trend towards higher surface atmospheric pressure in the region and a shift in large-scale weather patterns. There have been more highs, fewer lows and a reduction in the number of rain-producing lows and cold fronts. Over the southern Australia region, there has been an increase in density, and therefore frequency, of high pressure systems across all seasons.

Long-range forecast for May to July

The long-range forecast, released on 1 May 2025 for May to July 2025 shows:

• Rainfall is likely to very likely to be below average in parts of the south-west and south-east, the east, and much of the north.
• Warmer than average days and nights are very likely across most of Australia.

Deficiencies for the 4 months since January 2025

For the 4-month period since January 2025, areas with severe or serious rainfall deficiencies (rainfall totals in the lowest 5% or 10% of periods, respectively, since 1900) extend across:

• south-eastern South Australia
• western and south-western Victoria and part of south Gippsland
• most of Tasmania
• areas on the mid-west coast of Western Australia and a small pocket in the central interior.

Areas with lowest on record rainfall include:

• areas of South Australia within the Yorke Peninsula, Mid North and Upper South East districts
• coastline in Victoria from Warrnambool to Cape Otway
• north-west Tasmania.

Tasmanian area-averaged January to April rainfall was 48% below the 1961–1990 average, the driest start to the year on record since the national dataset began in 1900.

January to April 2025 mean maximum temperatures were highest on record across much of southern Australia and mean minimum temperatures were very much above average to highest on record across southern Australia.

Deficiencies for the 15 months since April 2023

For the 15-month period since February 2024, areas with severe or serious rainfall deficiencies (rainfall totals in the lowest 5% or 10% of periods, respectively, since 1900) extend across:

• agricultural regions of South Australia
• western, southern and parts of central and north-eastern Victoria
• a small area of the eastern ranges in southern New South Wales
• coastal western Tasmania and Bass Strait islands
• small areas along coastal south-west Western Australia.

Areas with lowest on record rainfall include:

• in South Australia, large areas of the Eyre Peninsula, Yorke Peninsula, Kangaroo Island, the Mid North and the Murraylands
• parts of Victoria's Mallee and Wimmera districts and much of the south-west coast
• part of the north-west coastline in Tasmania.

Compared to March, areas of rainfall deficiency increased in severity in south-eastern states, with areas of lowest on record expanding in South Australia and in western Victoria. Serious rainfall deficiencies have been largely removed in southern Western Australia following above average rain in March and April.

Deficiencies for the 25 months since May 2023

For the 25-month period since April 2023, which includes the last two southern cool seasons, areas with lowest on record, severe or serious rainfall deficiencies (record low rainfall totals or in the lowest 5% or 10% of periods, respectively, since 1900) extend across:

• large parts of the south-west of Western Australia
• agricultural regions of South Australia
• south-western Victoria
• parts of the west and east coasts of Tasmania, the Bass Strait islands, and some inland areas
• a small area of the south-eastern ranges in Victoria and New South Wales.

Areas with lowest on record rainfall include:

• a large region extending inland around Perth in Western Australia
• an area inland near Adelaide, and a small area on the Yorke Peninsula in South Australia
• the coastline from Warrnambool to Cape Otway in Victoria.

Since March, rainfall deficiency areas have increased in severity in South Australia, Victoria and Tasmania. The recent above average rainfall has eased, but not removed, the long-term deficiencies along the south-west coast of Western Australia.

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Below average soil moisture continues in the south

April root zone soil moisture was below to very much below average (in the lowest 10% of Aprils since 1911) in:

• much of the south-eastern mainland coastal region
• the central west of Western Australia
• Tasmania
• parts of south-eastern New South Wales.

Soil moisture is typically low at this time of year across much of southern Australia except for the east coast and Tasmania. However, there are long-term deficits across much of the region, particularly in south-east South Australia and western Victoria. With below average rainfall continuing across much of the south-east, soil moisture deficits in those areas have intensified and expanded from March. In western Tasmania the root zone soil moisture was around 20 to 30% below the typical column saturation for April.

Low soil moisture for long periods of time is an indicator of agricultural drought. It can affect ongoing crop growth, and the pasture growth required for livestock.

With significant rain in late March and above average rainfall in April, short-term soil moisture deficits were removed for most of northern Australia, south-east Queensland and northern New South Wales. Root zone soil moisture for April was above 50% saturation of the soil column for much of Queensland, the north of the Northern Territory and the central east coast.

High evaporative stress across much of southern Australia

Evaporative stress for the 4 weeks ending 30 April 2025 was elevated (negative Evaporative Stress Index (ESI)) in:

• southern South Australia
• Victoria excluding the far east
• Tasmania
• parts of western and south-east New South Wales
• Western Australia, excluding parts of the south-west and north.

April rainfall eased previously moisture-stressed areas in southern Western Australia, the Northern Territory, southern Queensland, northern South Australia and northern New South Wales. However, moisture stress intensified over much of the south, with areas of significantly elevated (below −2) ESI developing in south-eastern South Australia, western Victoria and northern Tasmania.

See this journal publication for further details on calculation and use of the ESI in drought monitoring.

Rainfall deficiencies and water storage at the end of April

• April rainfall was below average for Tasmania, Victoria, much of the east of South Australia and south-eastern New South Wales, and parts of the interior and the west of Western Australia.
• Rainfall deficiency areas increased in severity in south-eastern states.
• Areas of soil moisture deficiency continue across much of southern Australia.
• Streamflow was low at many sites in southern and western Australia.
• Many water storages in south-eastern states were 10 to 50% lower than the same time last year.
• Water storages for Adelaide and Perth are below 40% full.

Low streamflow in southern Australia

Lower than average streamflow (based on records since 1975) was observed in April at 25% of the 895 sites nationally with available data. These were observed in:

• the south-west of Western Australia (41% of 77 sites)
• the South Australian Gulf drainage division (80% of 10 sites)
• across the South East Coast, Victoria drainage division (50% of 93 sites)
• across Tasmania (90% of 22 sites).
• some sites in the south and north-east of the Murray–Darling Basin drainage division (28% of the 333 sites)
• across the Pilbara–Gascoyne (60% of 15 sites).

These were mostly associated with below average rainfall or dry catchment conditions. Very much below average streamflow (lowest 10% of years since 1975) was observed at 7% of sites, in:

• western and central east of Victoria and in the north and east of Tasmania
• south of the Murray–Darling Basin, and the South Australian Gulf drainage division
• the south-west of Western Australia.

April streamflow was average at 25% of sites, spread across Australia. Higher than average streamflow was observed at 49% of sites, including 26% of sites with very much above average streamflow (highest 10% of years since 1975), including:

• most of the sites across Queensland
• across the Carpentaria Coast drainage division
• east of the Lake Eyre Basin drainage division
• across the Tanami-Timor Sea Coast drainage division
• across the South East Coast, NSW drainage division
• north and a few sites in south of the Murray–Darling Basin
• a few sites in the south-west of Western Australia.

This was due to above average rainfall and high soil moisture and runoff in those catchments.

Low storage levels in the west, southern Australia, Murray–Darling Basin and central Queensland

By the end of April, the total water storage in Australia (across 306 public storages) was at 65.1% of capacity, 2.6% lower than the previous month and 12.7% lower than at the same time last year. Storage volumes decreased in April for 178 public storages and were relatively low in several regions including:

• the southern and eastern Murray–Darling Basin
• Victoria
• the South Australian Gulf drainage division
• central Tasmania
• central eastern Queensland
• Harding in the Pilbara-Gascoyne drainage division
• the Perth and Adelaide urban areas.

Storage volume decreases were generally in regions that had dry catchment conditions during April where inflows to storages were low.

Central Queensland

Storage volume decreased in March for many central Queensland storages such as Fairbairn and Lake Awoonga. The overall storage volume in the Nogoa-Mackenzie system, an important rural water supply for central Queensland communities, was 25.6% full at the end of April an increase by 2.6% from March and 14.5% from the same time last year. The water storage in Fairbairn was at 23.7% of capacity at the end of April, a 2.8% increase from March and a 15.1% decrease from the same time last year.

Southern and south-eastern storages

There has been a continued decline in storage levels in April for many storages in southern Australia, such as the Hume and in the Wimmera-Mallee. With dry catchment conditions and increased demand during the irrigation season (October to April), the storage volume decreased across the northern and southern Murray–Darling Basin. Combined storages in the Murray–Darling Basin were 54.9% full at the end of April, a 1.6% decrease from March and a 19.9% decrease from the same time last year. Menindee Lakes, in the west of New South Wales was 25.5% full at the end of April, a decrease of 1.1% from March and a 18.4% decrease from the same time last year.

Water storage in Hume dam, on the Murray River was at 21.1% of capacity at the end of April, a 4.4% decrease from March and a 39.2% decrease from the same time last year. In the Wimmera–Mallee system, a critical rural water supply to western Victoria for both domestic and agricultural purposes, storages were 36.8% full at the end of April, a 2.0% decrease from March and a 18.8% decrease from the same time last year.

Water storage in Great Lake in central-northern Tasmania, the second largest by capacity in the state, was 28.2% full at the end of the month, a 1.2% decrease from March and an increase of 7.4% from the same time last year.

Urban storages

At the end of April, the surface water storages supplying most capital cities were high (over 76% of their accessible capacity), with the exception of storages supplying Adelaide and Perth, which are below half capacity following extended periods of severe rainfall deficiencies. Perth's surface water storages were 36.9% full at the end of April, a 1.6% decrease from March, and a 0.3% increase from the same time last year. Adelaide's surface water storages were 35.5% full at the end of April, a 0.8% decrease from March, and a 9.5% decrease from the same time last year.

The long-term decline in surface water inflows to Perth's storages, as a consequence of reduced rainfall due to climate change, means the city's water supply is reliant on desalination and groundwater. Adelaide's water supply requirements are augmented by alternative sources. This is mostly by water transfer from the River Murray, and with some supply from desalination and groundwater. In South Australia, pipelines from the River Murray also augment water supply for the Eyre and Yorke Peninsulas and some of the south-east of the state. In response to developing rainfall deficiencies, the Victorian desalination plant commenced buffering surface water storage supplying Melbourne and Geelong.