Summary
The Department of Agriculture and Food, Western Australia’s Statistical Seasonal Forecast (SSF) system is indicating an above median rainfall outlook for the majority of the wheatbelt for March to May, autumn 2017.
- The SSF is indicating 60-100% chance of exceeding median rainfall for the majority of the wheatbelt, 40-60-% chance of exceeding median rainfall in some southern shires and Esperance and 30-40% for Manjimup and Denmark shires. Predictive skill based on February conditions is poor to moderate (50-70% consistent).
- The Bureau of Meteorology’s current seasonal outlook indicates that SWWA and the southern wheatbelt have 25-40% chance of exceeding the median rainfall for autumn. However, due to the decile 10 rainfall in February, soil moisture reserves are excellent for most parts of the wheatbelt. Predictive skill is poor to moderate (45-65% consistent).
- Temperature outlooks from the Bureau indicate a 55-75% chance of above normal day-time maxima and 45-65% chance of above normal night-time minima across the region for the March to May period (poor to moderate skill, 45-65% consistent).
- Rainfall in February was second highest for the South-West Land Division, behind 1955. Maximum temperatures were 1.6°C below average and the lowest since 2001, whilst minimum temperatures were near average.
Three month outlook for the south-west of Western Australia
Statistical Seasonal Forecasting (SSF)
DAFWA’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 the Seasonal Climate Information web page.
The SSF forecast for autumn, (March to May) 2017 is indicating 60-100% chance of exceeding median rainfall for the majority of the wheatbelt, 40-60% chance of exceeding median rainfall some Southern shires and Esperance and 30-40% for Manjimup and Denmark shires. The most probable decile range map indicates decile 8-10 rainfall for March to May for the northern and central wheatbelt, decile 2-3 for the south-west corner and decile 4-7 elsewhere. Predictive skill based on February conditions is poor to moderate (50-70% consistent).
