Climate outlook for October to January

Long-range forecast overview

The long-range forecast for October to December shows:

• Above average rainfall is likely across much of the western half of Australia.
• Rainfall is likely to be within the typical seasonal range for much of eastern Australia.
• Warmer than average days and nights are likely to very likely across most of Australia.

Our forecasts have greater accuracy closer to the forecast period. Refer to our weekly updates to follow the evolution of rainfall and temperature patterns as the October to December season approaches.

Rainfall—Summary

Rainfall likely to be above average across much of the west

October to December

• For much of the western half of the country, rainfall is likely (60 to 80% chance) to be above average across the next three months.
• Across parts of eastern Australia including much of NSW, eastern Victoria and inland and southern Queensland, and in WA's far south-west, rainfall is likely to be within the typical seasonal range.
• There is an increased chance of unusually high rainfall¹ for parts of the northern and southern mainland and eastern Tasmania.
• For October alone, above average rainfall is likely for most of WA, below average rainfall is likely for parts of the north, and much of the east is likely to have rainfall in the typical range for October.

¹Unusually high rainfall is defined as the highest 20% of observations for the forecast period (October to December) from 1981 to 2018.

Temperature—Summary

Increased chance of unusually warm days and nights across most of Australia

October to December

• Above average maximum and minimum temperatures are likely to very likely (60% to greater than 80% chance) across most of Australia.
• There is an increased chance of unusually high maximum temperatures² for most of Australia, with a greater chance across northern and western Australia, Victoria and Tasmania.
• There is an increased chance of unusually high minimum temperatures² across Australia, particularly across the north and in Tasmania where unusually high minimum temperatures are very likely.
• For October alone, maximum temperatures are likely to be in the typical seasonal range across parts of far eastern and central Australia but likely to very likely (60 to 80% chance) above average across the north, west and south-east.

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

We generate forecasts for up to 4 months ahead using our long-range forecast model, ACCESS-S. The model simulates the evolution of the state of the atmosphere and oceans for the coming months. It uses millions of observations from satellites and instruments on land and at sea.

We monitor global and hemispheric climate indicators that can support our understanding of longer-term predictability. These indicators are mainly associated with interactions between the atmosphere and ocean.

For general information, our monitoring of these climate indicators shows:

• Global SSTs persist at near-record warm temperatures, falling just short of the record temperatures observed during 2023 and well above all other years since observations began in 1854.
• The El Niño–Southern Oscillation (ENSO) is neutral.
• The Bureau's model suggests SSTs are likely to continue to cool but remain at ENSO-neutral levels. 6 other models were surveyed, and the other 3 suggest the possibility of SSTs in the tropical Pacific exceeding the La Niña threshold from October, and another 3 models forecast SSTs to fall just short of the threshold from November. All models forecast ENSO-neutral conditions by February 2025, suggesting that if a La Niña were to develop in the coming months, it is likely to be relatively weak and short-lived.
• The Indian Ocean Dipole (IOD) is currently Forecasts indicate that the IOD will likely remain neutral, but slightly negative, for the rest of the year. IOD events (positive or negative) are typically unable to form between December and April.