Warmer than average winter days are likely for most of Australia. Much of the east and west of the country has a very high chance (greater than 80%) of having warmer winter days.
Winter nights are likely to be warmer than average across WA, and parts of the north and east. For Central Australia, SA, and parts of inland southeast Australia, the chances of warmer or cooler winter nights are roughly equal.
Climate influences for this outlook include the increased chance of a positive Indian Ocean Dipole (IOD) event forming during winter, and a gradual weakening of the El Niño-like pattern in the tropical Pacific.
The current El Niño–like warmth in the central tropical Pacific Ocean is forecast to cool towards more ENSO-neutral levels in the coming months. As a result, the drying influence on Australian climate from a warm tropical Pacific will reduce over the season.
However, the Indian Ocean Dipole (IOD) is forecast to become positive from early winter. A positive IOD event typically brings drier conditions to much of southern and central Australia during winter-spring, meaning much of the winter dry signal is likely influenced by the forecast positive IOD.
The Bureau’s climate model also indicates that atmospheric pressures over much of southern and eastern Australia is likely to be higher than normal, with this signal strongest in June. This increases the chance of drier and warmer than average weather over much of southern and eastern Australia, and may keep cold fronts further to the south than normal.
In addition to the natural drivers such as ENSO and the IOD, Australian climate patterns are being influenced by the long-term increasing trend in global air and ocean temperatures.
Winter is likely to be drier than average for much of Queensland, NSW, Victoria, southeast SA, northern Tasmania, the NT, and northern and far southwest WA. The remainder of the country has roughly equal chances of a wetter or drier than average winter.
Historical outlook accuracy for winter is moderate for most of WA, Central Australia, western and southern Queensland extending into eastern NSW, western and central Victoria, and Tasmania. See map for details.
Warmer than average days are likely for most of Australia during winter, except for the far north of Queensland. For western and eastern parts of Australia, the chances of being warmer than average are very high; greater than 80%.
Nights are also likely to be warmer than average for WA, the northern NT, parts of Queensland, eastern NSW and most of Victoria and Tasmania. Chances of warmer or cooler nights are roughly equal across central Australia, SA, and inland southeast Australia. Regardless of the outlook for night-time temperatures, dry soils and the forecast for more cloud-free nights is likely to increase the risk of frost in susceptible areas.
Historical accuracy for June to August maximum temperatures is moderate to high across most of Australia, except the central NT, southern Queensland and northeast NSW, where accuracy is low. Minimum temperature accuracy is moderate across much of northern and eastern Australia, but patchy in WA, and low for inland southeast Australia. See map for more details.