Summary
The Department of Primary Industries and Regional Development’s (DPIRD) Statistical Seasonal Forecast (SSF) outlook for August to October, 2022 is indicating less than 40 % probability of above median rainfall for the South West Land Division.
- For August to October, the SSF forecast is indicating less than 40% probability of above median rainfall for the South West Land Division. The most likely decile range map is indicating decile 2-3 for the majority and decile 4-7 for South East Coastal forecast district. Skill is poor to good at 50 to 75 % consistent.
- The Bureau of Meteorology’s seasonal outlook for August to October 2022 is indicating 30-60% chance of exceeding median rainfall for the SWLD. The higher chances (55-65%) are for the South East Coastal Forecast District. Predictive skill is poor to good (45-75% consistent). The current longer-term outlook (at time of writing) for September to November 2022 is neutral (40-65%) chance of exceeding median rainfall with poor to moderate skill (45-65%).
- Temperature outlooks for August to October 2022, from the Bureau indicate a 55-80% chance of above average day-time maxima, with the higher chances along the coast. Skill is 75-100%. For night-time minima for the SWLD, the Bureau is indicating 60- 80% chance of exceeding above average temperatures, with the higher chances along the coast. Skill is poor at 55-75%.
- July rainfall was average to below average for the SWLD. July maximum temperatures were above average, with minimum temperatures average.
- The main climate driver influencing South West Land Division climate is the negative Southern Annular mode, which has brought rain in the first week of August. SAM is however, expected to return to being positive, which will have a drying influence for parts of south-west. The Indian Ocean Dipole (IOD) is currently negative and likely to remain through to November. Past negative IOD events generally increase rainfall in the eastern grainbelt.
Three Month Outlook for the south-west of Western Australia
Statistical Seasonal Forecasting (SSF)
DPIRD’s Statistical Seasonal Forecast (SSF) system uses historical relationships between global sea surface temperature and sea level pressure with rainfall in south-west Australia to produce forecasts of rainfall for the coming months. Users can click on any station indicated on the map for location-specific forecast information from DPIRD’s Seasonal Climate Information pages.
For August to October, the SSF forecast is indicating less than 40% probability of above median rainfall for the South West Land Division. The most likely decile range map is indicating decile 2-3 for the majority and decile 4-7 for South East Coastal forecast district. Skill is poor to good at 50 to 75 % consistent.
