South Pacific tropical cyclone season outlook

2013–2014 South Pacific tropical cyclone season outlook

Near average tropical cyclone season likely for the South Pacific

Chance of above average tropical cyclone (TC) activity

Region Summary Chance of
above average
Long-term average
number of TCs*
Whole South Pacific region Near average 48% 15
Western region Near average 56% 8
Eastern region Near average 47% 11

*averages may change when the dataset is updated.

This outlook is based upon the status of the El Niño - Southern Oscillation (ENSO) over the preceding July to September period. In 2013, neutral conditions were present during these months. In the absence of El Niño or La Niña (i.e., Neutral years), tropical cyclone numbers in the South Pacific region tend to be near average, though individual years can be above or below the long term mean.

The model has a high level of accuracy predicting cyclones in the western region , but less accuracy predicting cyclones in the eastern region. Regardless of the region or the skill of the statistical model, there is currently nothing in the broad climate drivers to suggest anything but a typical tropical cyclone season for the South Pacific region. This outlook is for the southern hemisphere tropical cyclone season which runs between 1 November and 30 April.
Related information: Tropical cyclone average conditions.

Past South Pacific tropical cyclone season outlooks

About the outlooks

This outlook is produced using statistical relationships between tropical cyclone numbers and two indicators: the Southern Oscillation Index (SOI) and the Niño3.4 sea surface temperature index (NINO3.4 SST). These indicators provide a measure of the strength of the atmospheric and oceanic state, respectively.

The July, August and September SOI and NINO3.4 values were used in making the South Pacific tropical cyclone season outlook.

2013 July August September
SOI +8.1 -0.5 3.9
NINO3.4 SST -0.31°C -0.28°C -0.03°C

The current status of ENSO can be viewed via the Bureau's ENSO Wrap-up. Tropical Pacific Ocean temperatures have been in a neutral state since October 2012. This means that the sea surface temperature patterns in the Pacific are neither La Niña nor El Niño and is therefore not driving the South Pacific region toward significantly more or fewer tropical cyclones than average. As such, the forecast is suggesting a season closer to average.

Further information