Summary
The Department of Primary Industries and Regional Development’s (DPIRD) Statistical Seasonal Forecast (SSF) outlook for spring, September to November 2021 is indicating more than 60% chance of exceeding median rainfall for the majority of the South West Land Division (SWLD).
- For spring, September to November, the SSF is indicating more than 60% chance of exceeding median rainfall for the majority of the South West Land Division (SWLD). The most probable rainfall decile map indicates decile 8-10 for the majority of SWLD. Predictive skill based on August conditions is mostly poor to good (50-75% consistent).
- The Bureau of Meteorology’s seasonal outlook for spring, September to November 2021 is indicating 35-55% chance of above median rainfall for the SWLD, with higher chances (60%) for Esperance. Predictive skill is moderate to good (55-75% consistent). The longer term outlook for October to December is generally neutral (45-55%) chance of exceeding median rainfall, with the higher chances (60%) for Esperance and lower chances (less than 35%) for the northern grain belt. Skill is poor to moderate (45-65%).
- Temperature outlooks for spring September to November 2021 from the Bureau indicate a 20-55% chance of above average day-time maxima (skill is moderate to good at 55-100%), lower chances for the southern coast and interior, and 20-40% chance of exceeding above average night-time minima for the SWLD (skill is poor to moderate 50-75%).
- August rainfall was below average to average for the SWLD. August maximum temperatures were above average and minimum temperatures were average to above average. There was widespread frost reported throughout the SWLD on 3 September.
- The main climate driver influencing the SWLD is higher than normal Mean Sea Level Pressure, and this pressure pattern will mean reduced westerlies into the South West, reducing rainfall and increasing the chance of frost.
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 spring, September to November, the SSF is indicating more than 60% chance of exceeding median rainfall for the majority of the South West Land Division (SWLD). The most probable rainfall decile map indicates decile 8-10 for the majority of SWLD. Predictive skill based on August conditions is mostly poor to good (50-75% consistent).
