Climate outlook for April to July

Long-range forecast overview

• For April to June, below median rainfall is likely to very likely (60% to greater than 80% chance) for the majority of Australia.
• April to June maximum temperatures are very likely (greater than 80% chance) to be warmer than median for most of Australia.
• April to June minimum temperatures are likely to very likely (60% to greater than 80% chance) to be warmer than median for south-western, far south-eastern and east coast Australia, as well as for northern Cape York Peninsula.
• This forecast is being influenced by several climate drivers including an ENSO-neutral pattern (neither El Niño nor La Niña) tending towards El Niño in the latter part of the forecast period, and the chance of a positive IOD later this year, as well as longer-term trends. An El Niño WATCH is current.

Drier than average April to June for the majority of Australia

• For April, below median rainfall is likely (60% to 80% chance) for most of Western Australia, South Australia, western and northern Victoria, western and central New South Wales, and areas near the southern Gulf of Carpentaria coast. Above median rainfall is likely for the northern Cape York Peninsula (60% to 80% chance) and some areas of eastern Queensland (60% to 65% chance).
• For April to June, below median rainfall is likely to very likely (60% to greater than 80% chance) for the majority of Australia. Exceptions are for the northern Cape York Peninsula, where above median rainfall is likely, and south-eastern parts of Queensland, coastal New South Wales and southern Tasmania, which have close to equal chances of above or below median rainfall.
• Past accuracy of April to June long-range forecasts for chance of above median rainfall has generally been high for most of western, northern, and eastern Australia, with moderate skill for much of southern Australia, extending into parts of the inland north-east of Western Australia and the south and inland west of the Northern Territory.

Warmer than average days for most of Australia during April to June

• For April, above median maximum temperatures are likely to very likely (60% to greater than 80% chance) for much of Australia except for most of Victoria along with southern and eastern New South Wales where maximum temperatures are equally likely to be above or below median.
• For April above median minimum temperatures are likely to very likely (60% to greater than 80% chance) for most of Western Australia, northern and eastern Queensland, Tasmania, Victoria, southern South Australia, and south-eastern New South Wales.
• April to June maximum temperatures are likely to very likely (60% to greater than 80% chance) to be above average across much of the country, excluding some areas of northern Queensland, central coastal New South Wales and central to north-eastern Victoria.

• April to June minimum temperatures likely to very likely (60% to greater than 80%) to be warmer than average most of Western Australia excluding the Kimberley, northern parts of the Northern Territory, northern Cape York Peninsula, the eastern Queensland coast, New South Wales east of the Great Dividing Range, Victoria, Tasmania and the far south-east of South Australia. Below median temperatures are likely (60 to 70% chance) for areas of central Australia and between the Flinders district in South Australia and western New South Wales.
• Past accuracy of the April to June chances of above median maximum temperature long-range forecasts has been moderate to very high across most of Australia. For minimum temperatures, accuracy has been moderate to high for most of Australia, with moderate to low skill for parts of mainland south-east Australia and southern and west coast Western Australia.

 Climate influences

Long-range forecasts reflect several significant climate influences. These include:

• While the Pacific Ocean is currently ENSO-neutral, there are some signs of El Niño forming later in the year. Hence the Bureau has issued an El Niño WATCH. This means there is around a 50% chance of an El Niño in 2023.
• General model guidance suggests a neutral ENSO (neither El Niño nor La Niña) will persist through autumn, with indications of potential El Niño development later in the year, however the Bureau's model is indicating an earlier transition, with El Niño thresholds potentially being reached in May. Long-range forecasts made during early autumn typically have lower accuracy than those made at other times of year.
• The Indian Ocean Dipole (IOD) is currently neutral. The majority of models suggest a positive event may develop in the coming months. Long-range forecasts for the IOD made during early autumn have lower accuracy than those made at other times of the year.
• The Southern Annular Mode (SAM) index is currently neutral and is expected to remain so over the coming weeks
• Sea surface temperatures are forecast to be warmer than normal in Tasman Sea, south of Tasmania, south-west of Western Australia and in parts of the Coral Sea
• The Madden-Julian Oscillation (MJO) is currently indiscernible. It is expected to re-strengthen over the Western Pacific region in early April. In the coming fortnight, the MJO is unlikely to have a large impact on rainfall patterns over northern Australia, although tropical activity across the south-west Pacific may become enhanced in early April.
• Longer-term trends: Australia's climate has warmed by around 1.47 °C in the period 1910–2021, leading to an increase in the frequency of extreme heat events. Southern Australia has seen a reduction of 10 to 20% in cool season (April–October) rainfall in recent decades.
• Since the 1990s, in the absence of strong 'wet' drivers, autumn rainfall in southern Australia has generally been drier than average. With most drivers easing in the coming months, a dry signal is starting to emerge.

The Bureau's climate model uses the physics of our atmosphere, oceans, ice, and land surface combined with millions of observations from satellites and on land and sea. As a result, it incorporates the influence of climate change and natural climate drivers like ENSO, IOD, the MJO, and SAM in its long-range forecasts.