Climate Model Summary

Models ease their La Niña likelihood for 2016

Tropical Pacific sea surface temperatures have been in the neutral range for several months now, and may remain neutral for the remainder of 2016. The latest outlooks have lowered their chances of La Niña forming later in the year. Two of the eight models surveyed maintain a La Niña outlook throughout the southern spring. Several other models approach La Niña thresholds, with some exceeding for brief periods. The Bureau's model outlook passes the La Niña threshold in August but returns to neutral levels for October and December.

All surveyed models agree the current negative Indian Ocean Dipole (IOD) is likely to persist until the end of the southern spring. Models suggest a return to neutral conditions by December; typical for the lifecycle of IOD events.

Along with ENSO and the IOD, very much above average sea surface temperatures around Australia may also influence our climate in the coming months.

NINO3.4 outlook

The latest NINO3.4 outlooks (initialised in July) show central tropical Pacific sea surface temperatures are likely to continue cooling, but remain within neutral thresholds for the later part of 2016. 

The all-model average NINO3.4 outlook for each month between August and the end of the year is between −0.5 °C and −0.6 °C, so remaining on the cool side of neutral, but not exceeding the La Niña threshold. Model ensembles are spread between La Niña and neutral scenarios for the remainder of the year; no model outlooks show a return to El Niño in 2016. 

The Bureau routinely monitors oceanic and atmospheric conditions and model outlooks. The most recent weekly NINO3.4 value to 17 July is −0.2 °C. NINO3.4 values below −0.8 °C typically indicate La Niña events.

Indian Ocean Dipole (IOD) outlook

The latest weekly IOD index value to 17 July is −1.3 °C, consistent with a strong negative IOD event (consecutive values at or below <−0.4 °C indicate a negative IOD). The latest surveyed models all agree negative values will persist until the end of spring. A negative IOD typically enhances rainfall over southern Australia during winter and spring. For more information on the establishment of the negative IOD in 2016, see the ENSO Wrap-Up.

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 17 July) suggests NINO3.4 will surpass La Niña thresholds (−0.8 °C) briefly during August and September but return to neutral values soon after. POAMA suggests values will remain on the cool side of neutral from October until the end of summer 2016-17. 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 17 July 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) -1.01 -0.87 -0.58 -0.43 -0.43 -0.46 -0.40
Model cool frequency (<−0.8°C) 90.91% 66.67% 18.18% 9.09% 3.03% 24.24% 12.12%
Model neutral frequency 9.09% 33.33% 81.82% 90.91% 96.97% 75.75% 87.88%
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.