The November to January climate outlook from the Bureau of Meteorology indicates large parts of Australia are likely to be drier than average.
- November, in particular, is likely to be drier than average in many areas. However, areas to the east of the Great Dividing Range show no strong indication of either a wetter or drier month.
- November to January days are very likely to be warmer than average for most of Australia. Nights are also likely to be warmer than average, except for areas surrounding the Great Australian Bight.
- A drier and warmer than average three months would mean a low chance of recovery for drought-affected areas of eastern Australia.
- Current observations and model outlooks indicate the chance of El Niño has increased and a positive Indian Ocean Dipole is likely underway.
- The tropical Pacific Ocean has been warming in recent weeks. The Bureau’s model indicates this warming will continue, with El Niño likely to develop before the end of the year.
- El Niño typically results in below-average spring rainfall for northern and eastern Australia, and warmer days for the southern two-thirds of the country. By summer, the rainfall influence from El Niño contracts to the tropical north, while warmer days remain likely for large parts of the country.
- It is likely that a positive Indian Ocean Dipole (IOD) event is underway, as 5 of the past 6 weeks have exceeded positive IOD thresholds. The Bureau’s model suggests positive IOD values will continue through October and return to neutral during November. A positive IOD typically decays in late spring or early summer. A positive IOD during spring typically reduces rainfall across much of the eastern two-thirds of Australia and can exacerbate any El Niño-driven rainfall deficiencies. During December to April, the IOD typically has little effect on Australian climate.
- Across northern Australian waters, sea surface temperatures have been average to cooler than average in recent months. This can lead to reduced rainfall as less atmospheric moisture is available for rain-bearing weather systems which move over the continent.
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.
Source: Bureau of Meteorology