Australia
Average: 11 TCs
Chance of more: 34%
The Australian tropical cyclone season:
In El Niño years:
Australia
Average: 11 TCs
Chance of more: 34%
Western region
Average: 7 TCs
Chance of more: 43%
Northern
region
Average: 3 TCs
Chance of
more:
46%
Northwestern
region
Average: 5 TCs
Chance of
more:
38%
Eastern
region
Average: 4 TCs
Chance of
more:
42%
Chance of above average tropical cyclone activity
Click map labels for region details. Large map
Region | Outlook summary (near, below or above average) |
Chance of above average |
Long-term average number of tropical cyclones |
---|---|---|---|
Australian | below average | 34% | 11 |
Western | near average | 43% | 7 |
Northwestern sub-region | below average | 38% | 5 |
Eastern region | near average | 42% | 4 |
Northern region | near average | 46% | 3 |
*Long-term average number of tropical cyclones may change slightly from one year to the next as a new season of data is added to the calculation.
This outlook is based upon the status of the El Niño–Southern Oscillation (ENSO) over the preceding July to September period. The Pacific Ocean has remained neutral during these months but the ocean temperatures have been near El Niño thresholds. The Southern Oscillation Index, a measure of the atmospheric component of ENSO, has been negative through this period. Climate models suggest there is still double the normal chance of El Niño occurring this summer (i.e., 50% chance).
The statistical outlook indicates that regions can expect average to below-average tropical cyclone activity this coming season.
The Australian region is likely to experience below average tropical cyclone activity during the 2014–15 season. The outlook indicates a 34% chance of having more tropical cyclones than average over the Australian region (meaning a 66% chance of having fewer tropical cyclones than normal). Past outlooks have shown that the Australian region outlook has a high level of accuracy.
The western region experiences an average of seven tropical during the tropical cyclone season. The outlook indicates near-average tropical cyclone activity is most likely this season, with a 43% chance of an above average (57% chance of below average) number of cyclones. Typically between one and three tropical cyclones in the western region will have an impact upon the coast. In the past the accuracy for forecasts in the western region has been low.
The northwestern sub-region, where tropical cyclones can impact coastal Western Australian communities, has a below average outlook for tropical cyclones this season (38% of above average, meaning a 62% chance of below average). Typically, five cyclones form or pass through this area each season. Around 40% of tropical cyclones in the northwestern sub-region impact on the coast at some stage in their life cycle. Forecast accuracy in this region is good.
The northern region also has a near average outlook for this season. In an average year the northern region usually sees two or three named storms and one or two tropical lows that become cyclones after moving into the western or eastern regions. About three quarters of the tropical cyclones in the northern region impact the coast. Forecast accuracy in this region is low.
The eastern region outlook indicates a near average tropical cyclone season is most likely (42% chance of above average, 58% chance of below average. About a quarter of tropical cyclones in the eastern region make landfall. Forecast accuracy in this region is low.
Percentages such as a 40% chance of having more tropical cyclones than average (60% chance of having fewer) mean that for every ten years with similar climate patters to those currently observed, four years would be expected to have an above-average number of tropical cyclones and six years would be expected to have a below-average number of tropical cyclones. On average, 11 tropical cyclones occur over the full Australian region, with four making landfall. Although there are often fewer tropical cyclones on average over the Australian region during El Niño years, there has never been an El Niño year without at least one tropical cyclone making landfall over the Australian coast.