Climate outlook for September to November

Issued 30 August 2018

Climate outlook overview

The spring (September to November) climate outlook, issued 30 August 2018, shows drier than average conditions are likely for southern Australia extending up through NSW (west of the divide) and into central Australia. September and October are likely to be drier than average more broadly across most of the country.
Spring days are likely to be warmer than average for Australia.
With clear skies likely, the risk of frost and cold nights continue in the south, but overall, warmer than average minimum temperatures are likely in many locations.
A drier and warmer than average spring would likely mean intensification of the existing drought conditions across parts of eastern Australia and an increase in bushfire potential.
The El Niño-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) are currently neutral. However, current observations and model outlooks indicate El Niño and a positive IOD could develop in spring. See the Climate Influences section for more information.

Spring (September to November) is more likely to be drier than average for southwest WA, most of SA, the southern NT, inland NSW (west of the divide), Victoria, Tasmania, and northern Queensland. Elsewhere, there are roughly equal chances of a wetter or drier than average three months, meaning there is no strong indication either way that it will be particularly wet or dry.
September is likely to be drier than average in western WA, the Top End and eastern parts of the NT, Queensland, northeast NSW, most of Tasmania, and Victoria as well as adjacent areas across the border in NSW and SA.
Much of eastern and southern mainland Australia have experienced a very dry winter and start to the year, so an outlook with increased chances of drier conditions indicates areas currently experiencing drought are less likely to see significant respite in the coming three months.
Historical outlook accuracy for September to November is moderate to high over most of the country, except for western WA where accuracy is low to very low. See map for more detail.

The above average daytime temperatures that have occurred across Australia so far in 2018 are likely to continue.
Spring days are likely to be warmer than average for Australia.
With clear skies likely, the risk of frost and cold nights continue in the south, but overall, warmer than average minimum temperatures are likely in many locations.
Historical accuracy for September to November maximum temperatures is moderate to high for most of the country. Minimum temperature accuracy is moderate for eastern Australia, the Top End of the NT, and parts of central Australia. Elsewhere, accuracy is either patchy or low to very low.

The El Niño-Southern Oscillation is currently neutral, but there is a 50% chance (double the normal risk) of El Niño forming in the coming months. El Niño typically means below average rainfall during spring for northern and eastern Australia, and warmer days for the southern two-thirds of the country.
Similarly the Indian Ocean Dipole (IOD) is also neutral. However, outlooks suggest a brief positive IOD event may form during spring. A positive IOD during spring typically reduces rainfall in central and southern Australia, and can exacerbate any El Niño driven rainfall deficiencies.
Sea surface temperatures continue to be cooler than average to Australia's northwest, which is likely acting to suppress rainfall over southern and central Australia.
In addition to the natural drivers such as the El Niño–Southern Oscillation and the IOD, Australian climate patterns are being influenced by the long-term increasing trend in global air and ocean temperatures.
Bureau climatologists continually monitor the climate for any significant developments, with information on El Niño/La Niña and IOD events available fortnightly via the ENSO Wrap-Up. For a summary of Pacific and Indian Ocean outlooks, please see the Climate Model Summary.

Product code: IDCKOATCO2