Seasonal Climate Outlook

Recent climate

February rainfall was below average. February maximum temperatures were average to above average. Minimum temperatures were average. Rainfall since the start of the year has been below average for the majority of the SWLD.

Rainfall decile map 1 January to 6 March  2023, indicating decile 2-3 for the majority of the South West Land Division.
Rainfall decile map 1 January to 6 March 2023 for the South West Land Division

In February the atmospheric pressure was below normal over the SWLD.

Sea surface temperatures in February are near normal around Australia. The sea surface temperature outlook for March to May by the Bureau of Meteorology indicates SSTs will be normal to warm around Western Australia. Warmer temperatures marginally increase the likelihood of tropical cyclones developing.

The Indian Ocean Dipole (IOD) is neutral and has little influence on Australian climate while the monsoon trough is in the southern hemisphere (typically December to April). Two models (including the Bureau of Meteorology) are indicating the development of a positive IOD in May. While some models suggest positive IOD values may emerge during winter, IOD forecasts made at this time of the year have low accuracy when forecasting through the autumn.

The Southern Annular Mode (SAM), also known as the Antarctic Oscillation (AAO), describes the north–south movement of the westerly wind belt that circles Antarctica, dominating the middle to higher latitudes of the southern hemisphere. The Southern Annular Mode (SAM) is currently neutral and is forecast to remain neutral until the end of March. For more information see the Bureau of Meteorology’s Climate Driver Update.

The La Niña continues in the tropical Pacific. However, oceanic indicators of ENSO have returned to neutral values, with atmospheric indicators now also weakening. While models suggest there is an increased in risk of El Niño developing in June, model accuracy when forecasting through autumn is low, and ENSO outlooks that extend past autumn should be viewed with caution.

The table below gives a summary of past month and three-month South West Land Division (SWLD) climate conditions, and can indicate what is likely to occur in the near future if climate conditions follow the current pattern.

Climate Indicator Past month Past 3 months
SWLD Rainfall Below average Below average
SWLD Mean Temperature Above average to average Mixed
SWLD atmospheric pressure Below normal Below normal
Indian Ocean Sea surface temperature Warmer Warmer
El Niño/Southern Oscillation (ENSO) Neutral Neutral
Southern Annular Mode (SAM) Neutral Positive