Recent climate
February rainfall was generally below average to average for the SWLD. Some parts of the grainbelt received good falls in February: eastern locations Bonnie Rock and Merredin 30mm, Westonia 44mm and Latham in the north with 60mm. February maximum temperatures were very much above average for the SWLD. Minimum temperatures were above average. Rainfall since 1 January has been restricted to parts of the north and eastern grainbelt and along the south coast. Latham, in the Central West forecast district, has had 63mm since the start of the year.
In February the atmospheric pressure was slightly higher than normal over the SWLD.
In February, the Indian Ocean sea surface temperatures north-west of Western Australia were warmer than normal.The March to May 2022 SST forecast, by the Bureau of Meteorology indicates SSTs are likely to remain warmer than normal north-west and west of WA.
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. SAM is currently positive and is forecast to remain slightly positive until start of April. In a positive SAM phase, the belt of westerly winds contracts towards Antarctica. SAM has little influence on SWLD rainfall at this time of the year, a positive SAM increases temperature as there are fewer westly winds. For more information see the Bureau of Meteorology’s Climate Driver Update.
The Indian Ocean Dipole (IOD) is neutral. It typically has little influence on global climate from December to April due to the influence of the monsoon.
The 2021–22 La Niña is past its peak. Autumn is the usual time of the year in which ENSO events decay and return to neutral. La Niña increases the likelihood of tropical cyclones within the Australian region.
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 three months |
|---|---|---|
| SWLD Rainfall | Generally average | Below average |
| SWLD Mean Temperature | Very much above average | Very much above average |
| SWLD atmospheric pressure | Higher | Higher |
| El Niño/Southern Oscillation (ENSO) | La Niña | La Niña |
| Indian Ocean Dipole (IOD) | Neutral | Neutral |
| Southern Annular Mode (SAM) | Positive | Positive |