Summary
The Department of Primary Industries and Regional Development’s (DPIRD) Statistical Seasonal Forecast (SSF) outlook for November 2021 to January 2022 is indicating less than 40% chance of exceeding median rainfall for the majority of the South West Land Division (SWLD).
- For November 2021 to January 2022, the SSF is indicating less than 40% chance of exceeding median rainfall for the majority of the South West Land Division (SWLD). The most probable rainfall decile map indicates decile 2-3 for the majority of SWLD. Predictive skill based on October conditions is mostly poor to moderate (50-70% consistent).
- The Bureau of Meteorology’s seasonal outlook for November 2021 to January 2022 is indicating 35-55% chance of above median rainfall for the SWLD. Predictive skill is poor to good (55-75% consistent). The longer term outlook for December 2021 to February 2022 is drier for the central grain belt. Skill is poor to moderate (45-65%).
- Temperature outlooks for November 2021 to January 2022, from the Bureau indicate a 20-55% chance of above average day-time maxima (with the lower chances for the Great Southern and South Coastal forecast districts). Skill is good at 75-100%. The Bureau indicates mostly neutral chances, at 35-55%, of exceeding above average night-time minima for the SWLD. Skill is good 65-100%.
- October rainfall was above average for the SWLD. October maximum and minimum temperatures were below average, with some frost damage reported in Wickepin and Kojonup on 6 October.
- The main climate driver influencing the SWLD is the positive Southern Annular Mode, which is forecast to stay positive for the rest of the year. In a positive SAM phase, the belt of westerly winds contracts towards Antarctica. This results in weaker than normal westerly winds and higher pressures over southern Australia, restricting the passage of cold fronts inland.
Three month outlook for SWLD 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 SWLD 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 November 2021 to January 2022, the SSF is indicating less than 40% chance of exceeding median rainfall for the majority of the South West Land Division (SWLD). The most probable rainfall decile map indicates decile 2-3 for the majority of SWLD. Predictive skill based on October conditions is mostly poor to moderate (50-70% consistent).
