Long-range forecast overview

The long-range forecast for March to May shows:

• Rainfall is likely to be below average for most of southern Australia, and above average in the north.
• Daytime temperatures are very likely to be above average across most of the southern two-thirds of Australia and parts of far northern Australia.
• Overnight temperatures are likely to very likely to be above average across much of Australia.

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Rainfall—Summary

Below average autumn rainfall likely for most of the south, above average in the north

March to May

• Autumn rainfall as a whole is likely to be below average (60 to 80% chance) for most of southern Australia, except parts of the east coast.
• There is no clear forecast signal in March for most of southern Australia, with a drier-than-average forecast signal strengthening and expanding to cover much of Australia from April.
• Above average autumn rainfall is likely (60 to 75% chance) for parts of northern Australia including Cape York Peninsula and central parts of the Northern Territory, largely due to the strong signal for above average rainfall in March.
• There is an increased chance of unusually low rainfall¹ (over 40% chance) for parts of Victoria and south-western Western Australia from April onwards.

¹Unusually low rainfall is that in the driest 20% of March to May records between 1981 and 2018

Temperature—Summary

Warmer than average autumn days and nights likely across much of Australia

March to May

• Maximum temperatures for autumn are very likely to be above average (more than 80% chance) across most of the southern two-thirds of Australia and parts of far northern Australia.
• The chance of above average maximum temperatures is closer to 50% for northern parts of Queensland, Western Australia and the Northern Territory, with below average maximum temperatures likely (60 to 75% chance) for some regions. Rainfall and increased cloud cover, particularly during March, increases the chance of below average maximum temperatures.
• Much of the southern half of Australia has an increased chance of unusually high maximum temperatures² (over 40% chance), with the strongest chances in north-eastern Tasmania and south-western parts of Western Australia (over 70% chance).
• Minimum temperatures are likely (60% to greater than 80% chance) to be above average across much of Australia, with lower chances (closer to 50%) across parts of Australia's north, south-east and interior.
• There is an increased chance of unusually high minimum temperatures² (over 40% chance) for parts of the east coast and western parts of Western Australia.

²Unusually high maximum and minimum temperatures are those in the warmest 20% of March to May days and nights, respectively, between 1981 and 2018.

We use our long-range model, ACCESS-S, to forecast up to four months ahead. It simulates how the atmosphere and oceans may change, using millions of observations from satellites, land stations, and ocean instruments.

We also track global climate indicators to help understand long-term weather patterns. These mainly reflect how the ocean and atmosphere interact.

Current climate indicators:

• Sea surface temperatures (SSTs) during January 2026 were the sixth warmest on record in the Australian region and the fourth warmest for the global average.
• The SST analysis for the week ending 22 February 2026 shows warmer than average waters (up to 2 °C above average) persist off the NSW coast. Elsewhere in the Australian region, SSTs have warmed over the Coral Sea and coastal waters of Australia's east coast and cooled over waters to the west and north of Australia, compared to last week.
• Forecasts for March to May indicate warmer-than-average SSTs are likely for much of the region, especially off southern Australia. Warmer oceans can provide increased moisture and energy, that can enhance the severity of storms, cyclones and rain systems.
• The 2025–26 La Niña continues to weaken. Sea surface temperatures in the central tropical Pacific have been fluctuating around the La Niña threshold (−0.80 °C) since late January. Recent warming in the sub-surface suggests further decline of the event is likely in the coming weeks.
• While some models suggest the possibility of El Niño development from June, forecasts beyond autumn remain highly uncertain. The large spread of outcomes across models reflects the low predictability at long lead times typical for this time of year, with reliability expected to improve as autumn progresses.
• The Indian Ocean Dipole (IOD) is neutral despite elevated IOD index values over the past few weeks. IOD events do not typically form during December to April, and these positive values are not expected to be sustained or at levels strong enough to form an event. Model forecasts expect the IOD to remain in a neutral state until at least the end of autumn 2026.