Climate outlook for April to June
Issued 30 March 2017
Climate outlook overview
- April to June rainfall is likely to be below average over the southern two-thirds of mainland Australia excluding the east coast, and above average for the far north.
- April is likely to be drier than average across the south and southwest of Australia, but wetter for eastern NSW, southeast Queensland and far northern Australia.
- Daytime temperatures for April to June are likely to be above average for most of Australia, except parts of eastern and northern Australia.
- Night-time temperatures for April to June suggest a warmer three months for many parts of Australia, except northern WA and the Top End of the NT, where cooler than average nights are more likely. Additionally, southern WA, southern SA, eastern NSW and Cape York Peninsula show roughly equal chances of cooler or warmer April to June nights.
- In Tasmania, the chances of warmer than average daytime and overnight temperatures are very high (greater than 80%) for April, and for April to June.
- Outlooks are influenced by warming in tropical Pacific sea surface temperatures and a cooler eastern Indian Ocean (see the Climate Influences section for more detail).
Drier April to June likely for southern two-thirds of Australia
- April is likely to be drier than average in the central, south and southwest of Australia, but wetter for eastern NSW, southeast Queensland and far northern Australia.
- April to June rainfall is likely to be below average over the southern two-thirds of Australia, except the east coast and most of Tasmania. Rainfall is likely to be above average for the far north.
- Outlooks are influenced by warming of tropical Pacific sea surface temperatures, a cooler than average eastern Indian Ocean, and some cooling of the Coral Sea.
- Historical outlook accuracy for April to June is generally moderate to high over most of Australia, but low in Tasmania and small patches across the south. See map for more detail.
Warmer season likely for much of Australia, but cooler for tropical north
- Daytime temperatures for April to June are likely to be above average for most of Australia, except parts of eastern and northern Australia.
- Night-time temperatures for April to June are also likely to be warmer for most of Australia, except northern WA and the Top End of the NT, where cooler than average nights are more likely. Additionally, southern WA, southern SA, eastern NSW and Cape York Peninsula show roughly equal chances of cooler or warmer April to June nights.
- Outlooks are influenced by warming of tropical Pacific sea surface temperatures and a cooler than average eastern Indian Ocean.
- Historical maximum temperature accuracy for April to June is moderate to high over most of Australia. Minimum temperature accuracy is also moderate to high for most of the country, except parts of southwestern WA, where accuracy is moderate to low.
Climate influences
- The El Niño–Southern Oscillation (ENSO) remains neutral, but tropical Pacific Ocean waters have been steadily warming, adding 0.5 °C since January. The Bureau's climate model suggests El Niño conditions are likely to develop during winter—in line with most international climate models surveyed by the Bureau. However, some caution should be exercised as models have lower accuracy at this time of year in forecasting El Niño. El Niño typically biases Australia's climate towards a drier than average winter-spring, and warmer daytime temperatures in the south.
- The Indian Ocean Dipole (IOD) remains neutral. The IOD has little influence on Australia from December to April. Outlooks suggest the IOD will remain neutral for at least the next three months. However, slightly cooler than average temperatures are forecast for the central parts of the tropical Indian Ocean, which may have some effect upon Australian conditions.
- The model forecasts a cooling of waters in the Coral Sea during the season, which may bring reduced rainfall in adjoining regions.
- The wetter than average conditions likely for northern and eastern Australia during April are likely a result of rain forecast for early in the month.
- The past two decades have seen autumn (March to May) rainfall declines across much of southern Australia. Of the past 26 years, 22 years have seen below-average rainfall across southeast 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.
