Climate Model Summary

La Niña development likely in austral winter 2016

The tropical Pacific has continued to cool. Climate models indicate this cooling trend is expected to continue, with six out of eight models suggesting La Niña is likely to form during the austral winter. However, one of these six models indicates this may be only a short-lived event.

The Indian Ocean Dipole (IOD) outlooks suggest a negative IOD may develop during winter. However, model skill is low at this time of year, so caution should be exercised when using these forecasts.

While ENSO and the IOD can be strong influences on Australian climate at certain times of year, other factors may also influence our climate —see our Climate Outlooks page for the latest rainfall and temperature outlooks.

NINO3.4 outlook

The latest NINO3.4 outlooks (initialised in May) indicate that sea surface temperatures across the central tropical Pacific Ocean are likely to continue cooling into the austral winter.

The all-model average NINO3.4 outlook for June is −0.7 °C; just above the La Niña threshold of −0.8 °C. By August, the model average drops to −1.2 °C, but then levels off to −1.1 °C in October.

Six out of eight models indicate La Niña will form, but the POAMA model suggests only a short-lived La Niña. A seventh model (ECMWF) briefly falls into La Niña levels during July, but does not maintain its strength for long enough to be considered an event.

Oceanic and atmospheric conditions as well as the model outlooks will be monitored closely during the ENSO transition period. The most recent NINO3.4 value is +0.3 °C for the week ending 22 May 2016. NINO3.4 values above +0.8 °C (below −0.8 °C) typically indicate El Niño (La Niña) events.

Indian Ocean Dipole (IOD) outlook

The Indian Ocean Dipole (IOD) can affect Australian climate from May to November. Current outlooks (initialised in May) all suggest a negative IOD is likely to develop during winter. However, outlook accuracy for the IOD at this time of year is low. A negative IOD typically enhances rainfall over southern Australia during winter and spring.

The most recent IOD index value is −0.3 °C for the week ending 22 May 2016. Sustained IOD index values below −0.4 °C typically indicate a negative IOD event.

Predictive Ocean Atmosphere Model for Australia (POAMA)

POAMA, run at the Bureau of Meteorology, generates an eight-month forecast each fortnight. The most recent model run (generated 22 May) suggests NINO3.4 will cool rapidly during May, exceeding La Niña thresholds in July, return to neutral levels in September, and maintain values close to the La Niña threshold until the end of the year. The forecast values, shown below in bold, are for POAMA's ensemble mean.

Product code: IDCKGL0000

Australian climate is influenced by temperature patterns in the Pacific and Indian Oceans. This page provides information on Pacific and Indian Ocean outlooks for the coming six months based on a survey of international climate models. It is updated monthly.

Further details: ENSO Wrap-Up (ENSO and IOD); Climate Outlooks

Average of international model outlooks for NINO3.4

Graphs based on the ensemble mean for the most recent model run.

The arrows on the dials above indicate the combined average of monthly NINO3.4 outlooks from a survey of international global climate models. Note that the individual model runs vary around the average.

More information:

NINO3.4 covers the central Pacific region.

Graphs

Nino 3.4 2 month outlook Models information
Graph details

The graphs are based on the ensemble mean for the most recent model run.

These graphs show the average forecast value of NINO3.4 for each international model surveyed for the selected calendar month. If the bars on the graph are approaching or exceeding the blue dashed line, there is an increased risk of La Niña. Similarly, if the bars on the graph are approaching or exceeding the red dashed line, there is an increased chance of El Niño.

Graphs

Latest POAMA IOD outlook Models information
Graph details

The graphs are based on the ensemble mean for the most recent model run.

Thse graphs show the average forecast value of the IOD index for each international model surveyed for the selected calendar month. If the majority of models are approaching or exceeding the blue dashed line, then there is an increased risk of a negative IOD event. If the majority of models are approaching or exceeding the red dashed line, then there is an increased risk of a positive IOD event.

POAMA Long-Range Outlook

Issued 22 May 2016

Updated fortnightly

These model forecasts of the El Niño – Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) are generated by the Predictive Ocean Atmosphere Model for Australia (POAMA), a dynamical computer model of the climate system run at the Bureau of Meteorology. They are included in the monthly model summary of predictions from POAMA and other models operated by international organisations.

POAMA outlooks provide forecasts out to nine months ahead. The model ensemble distributions shown here provide a range of possible developments in sea surface temperature (SST) in the equatorial Pacific Ocean (NINO regions) and for the Indian Ocean.

NINO34 predictions for the next 9 months.

Skip to past graph to table of values

Outlook graph for selected indice

NINO34 probabilities

Click dates in the first row to see probability graphs
Outlook for month
NINO34 (°C) -0.65 -1.07 -1.03 -0.79 -0.66 -0.63 -0.64
Model cool frequency (<−0.8°C) 18.18% 84.85% 69.7% 39.39% 27.27% 24.24% 21.21%
Model neutral frequency 81.82% 15.15% 30.3% 60.61% 72.73% 75.76% 78.79%
Model warm frequency (>+0.8°C) 0% 0% 0% 0% 0% 0% 0%

More information:

Model details

The models used within our survey are listed below with links to their agency homepages, model output and technical information about the model.

Model data are provided for Bureau of Meteorology use by the agencies detailed in the Models section. Respective agency copyright applies to these data.