Climate outlook for winter (June to August)
Issued 25 May 2017
Climate outlook overview
- Winter (June to August) rainfall likely to be below average over the southern half of mainland Australia.
- A drier than average June is likely over much of WA, SA and western parts of NSW and Victoria.
- Winter daytime temperatures are likely to be warmer than average for the southern half of Australia and the tip of Cape York Peninsula.
- Night-time temperatures during winter are likely to be warmer than average for southern WA, parts of southeast Australia, and the tip of Cape York Peninsula.
- This outlook is influenced by warmer than average tropical Pacific sea surface temperatures and a cooler eastern Indian Ocean (see the Climate Influences section for more detail).
Drier winter likely for most of southern Australia
- June is likely to be drier than average over southern and central WA, SA and western parts of NSW and Victoria.
- Winter (June to August) rainfall is likely to be below average over the southern half of mainland Australia. While there is a tendency for eastern Tasmania to be wetter than average for winter, model accuracy in eastern Tasmania for this period is low.
- The Top End of the NT is likely to have a wetter June to August, but it is now the dry season, and median rainfall at this time of year is very low. Only a small amount of rainfall—which could come from a single rain event—would be needed to exceed the median.
- Outlooks are being influenced by warmer than average tropical Pacific sea surface temperatures and a cooler than average eastern Indian Ocean.
- Historical outlook accuracy for June to August is moderate over western WA, northeast Australia, and western Tasmania, with low accuracy elsewhere. See map for more detail.
Warmer winter days likely for southern States
- Daytime temperatures for June to August are likely to be warmer than average for the southern half of Australia and the tip of Cape York Peninsula.
- Night-time temperatures for June to August are likely to be warmer for southern WA, southeast SA, eastern NSW, Victoria, Tasmania and the tip of Cape York Peninsula. Most of the country has roughly equal chances of warmer or cooler winter nights.
- Outlooks are being influenced by warmer than average tropical Pacific sea surface temperatures and a cooler than average eastern Indian Ocean.
- Historical maximum temperature accuracy for winter is moderate to high over most of Australia, except much of WA, and western and southern SA. Minimum temperature accuracy is moderate for most of Australia.
Climate influences
- The El Niño–Southern Oscillation (ENSO) remains neutral, but tropical Pacific Ocean waters are warmer than average. The Bureau's climate model suggests further warming is unlikely, with outlooks falling short of El Niño levels. The majority of international climate models surveyed by the Bureau still suggest El Niño will develop later this year. During El Niño, winter-spring rainfall tends to be below average in eastern Australia, while warmer than average daytime temperatures are likely in the south. Some El Niño-like effects may still be felt even if an event doesn't fully develop, but Pacific Ocean temperatures remain warmer than average.
- The Indian Ocean Dipole (IOD) remains neutral. Outlooks from the Bureau's climate model suggest the IOD will remain neutral for at least the next three months. However, slightly cooler than average temperatures are forecast for the central to eastern parts of the tropical Indian Ocean, which may affect Australian rainfall patterns.
- Additionally, higher than average pressure is forecast for southern parts of Australia, which means fewer cold fronts and low pressure systems are likely to cross southern Australia during winter.
- 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.
