Climate Model Summary

Neutral ENSO and IOD set to continue for 2017

The El Niño-Southern Oscillation (ENSO) is neutral. All eight models suggest that sea surface temperatures in the tropical Pacific Ocean will fall short of El Niño thresholds in 2017 with ENSO-neutral as the most likely outcome for the remainder of the year.

The Indian Ocean Dipole (IOD) is currently neutral with two out of six models meeting positive IOD thresholds in August, with only one model persisting at these thresholds through to October. A positive IOD is typically associated with below average winter-spring rainfall over southern and central Australia.

NINO3.4 outlook

The latest outlooks suggest that the central tropical Pacific Ocean will remain at temperatures consistent with a neutral ENSO throughout the forecast period, with eight models maintaining neutral values into December 2017. This is in contrast to model outlooks from earlier in the year that suggested an increased chance of El Niño developing during 2017.

While sea surface temperatures (SSTs) in the central tropical Pacific have been warmer than average since the beginning of the year, the NINO3.4 SST index has remained consistently within ENSO-neutral values. The most recent weekly NINO3.4 value (to 16 July) is +0.5 °C.

The Bureau routinely monitors oceanic and atmospheric conditions and model outlooks. NINO3.4 values that persist below −0.8 °C typically indicate La Niña, while persistent values above +0.8 °C typically indicate El Niño.

Indian Ocean Dipole (IOD) outlook

The latest weekly IOD index value to 16 July is –0.1 °C, within neutral boundaries. Two of the six surveyed models suggest index values may meet or exceed the positive IOD threshold of +0.4 °C during August, with only one model persisting at these thresholds through to October. A positive IOD is typically associated with below average winter-spring rainfall over southern and central Australia.

Index values above the positive IOD threshold would need to be sustained for at least eight weeks for 2017 to be classified as a positive IOD year.

 

Predictive Ocean Atmosphere Model for Australia (POAMA)

POAMA, run at the Bureau of Meteorology, generates a nine-month forecast each fortnight. The most recent model run (generated 16 July) indicates NINO3.4 will cool during August, but remain neutral throughout the forecast period.

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.

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

Average of international model outlooks for NINO3.4

Average of international model outlooks for the Indian Ocean Dipole (IOD)

Based on the ensemble mean for the most recent model run.

The arrows on the dials indicate the combined average of monthly 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 16 July 2017

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) -0.70 -0.54 -0.30 -0.29 -0.33 -0.34 -0.22
Model cool frequency (<−0.8°C) 21.21% 9.09% 0% 0% 9.09% 9.09% 12.12%
Model neutral frequency 78.79% 90.91% 100% 99.99% 90.9% 90.9% 87.88%
Model warm frequency (>+0.8°C) 0% 0% 0% 0% 0% 0% 0%

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.