Long-range forecast overview

The long-range forecast for December to February shows:

• Rainfall is likely to be below average for parts of the west; the forecast signal is weak in the east, meaning roughly equal chances of above or below average rainfall.
• Daytime temperatures are likely to be above average across most of Australia.
• Overnight temperatures are very likely to be above average across most of Australia.

Rainfall—Summary

Rainfall is likely to be below average for parts of the west; the forecast signal is generally weak in the east.

December to February

• For much of eastern Australia, there is roughly an equal chance of above or below average rainfall, over the three months to February.
• Rainfall is likely to be below average (60 to 80% chance) for parts of the western half of the mainland.
• Chances of above average rainfall have generally decreased over recent forecasts, with a dry signal now more pronounced for the month of December.
• During November and December, northern Australia typically experiences increasing storms and showers as the wet season advances. Tropical Australian rainfall typically peaks in the January to March period.

Temperature—Summary

Warmer than average days and nights likely across most of Australia

December to February

• Maximum temperatures are likely to be above average (60% to over 80% chance) across most of Australia.
• There is an increased chance of unusually high maximum temperatures¹ (over 50% chance) across much of north-west and western Australia, as well as parts of south-eastern South Australia, extending into much of Victoria and Tasmania.
• Minimum temperatures are very likely to be above average (over 80% chance) across much of Australia.
• There is an increased chance of unusually high minimum temperatures¹ (over 50% chance) across northern Australia and Tasmania, with the strongest chances in the tropical north (over 80% chance).

¹Unusually high maximum and minimum temperatures are those in the warmest 20% of December to February 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:

• Since July 2024, sea surface temperatures (SSTs) in the Australian region have been the warmest or second warmest on record for each respective month. Similarly, global SSTs remain substantially above average, with October 2025 the third warmest on record.
• SSTs for the week ending 16 November 2025 were warmer than average across much of the Australian region, particularly in the Coral Sea. SSTs were cooler than average across southeastern coasts.
• Forecasts for December to February show warmer-than-average SSTs are likely around most of Australia, especially to the south-east. Warmer oceans can provide increased moisture and energy, that can enhance the severity of storms, cyclones and rain systems.
• El Niño–Southern Oscillation (ENSO) remains neutral but there are signs La Niña may be developing. Atmospheric and oceanic indicators have shown some signs of La Niña development since at least mid-to-late September.
• The Bureau's model currently predicts that tropical Pacific Ocean temperatures are likely to just meet La Niña levels till at least January, before returning to neutral in mid-to-late summer. This timing aligns with most international models assessed.
• The negative Indian Ocean Dipole (IOD) event remains active but is likely to be weakening. The Bureau's model predicts a return to neutral in December, which is consistent with most international models.