Climate outlook for winter (June to August)

Issued 28 May 2015

Climate outlook overview

A generally drier and warmer-than-normal winter in the east, but a cooler, wetter season more likely over southern WA.
Both the Pacific and Indian oceans are influencing this outlook. The El Niño in the Pacific (which models indicate will strengthen) is having a drying impact on eastern Australia, while continued warmth in the Indian Ocean, coupled with the El Niño in the Pacific, is tending to enhance rainfall in southern WA.

Winter is more likely to be drier than normal in southern and inland Queensland, northern and eastern NSW, eastern Victoria and western Tasmania. A dry signal is also evident in the northern tropics, although it is seasonally dry in this region at this time of year.
A wetter-than-normal winter is likely for the southern half of WA. Odds for above average winter totals are close to 50% for the remainder of the country (see map).
There are two main climate influences for the current outlook. Elevated sea surface temperatures in the Indian Ocean, coupled with warm temperatures in the tropical Pacific Ocean, are tending to enhance rainfall in WA. The El Niño pattern in the tropical Pacific is having a drying influence in the eastern half of the country.
Outlook accuracy for winter is moderate over the southern half of WA, and much of eastern Australia. However, in northern WA, central Australia and much of SA and Victoria, historical accuracy is low.

Winter days are more likely to be warmer than normal over the tropical north and the eastern half of Australia, particularly in Tasmania. Parts of inland WA may see a cooler season.
Winter nights are more likely to be warmer than normal across much of Australia, except in parts of inland NSW and WA.
The major climate influences for the season ahead are the El Niño in the Pacific and warmer-than-normal sea surface temperatures in the Indian Ocean.
Maximum temperature accuracy is moderate to high over most of Australia, excluding parts of inland WA where skill is low to very low. Minimum temperature accuracy is moderate to high over most of the country.

The El Niño in the tropical Pacific continues to strengthen.
Sea surface temperatures (SSTs) in the Indian Ocean remain higher than normal. This pattern of SSTs, coupled with the warm SSTs in the Pacific is tending to enhance rainfall in the southern half of WA. The drying influence of El Niño is impacting on the eastern half of the country.
Climate models suggest that the tropical Pacific will continue to warm throughout winter and spring, with the El Niño continuing to strengthen.
Some, but not all, models suggest an increased chance of a positive Indian Ocean Dipole (IOD) event developing later in 2015. Positive IOD events are typically associated with decreased winter and spring rainfall over southern and central Australia.
The Australian tropics are now in their dry season; much of this region receives less than 10 mm of rain on average over the winter months.
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.