Seasonal Climate Outlook

Summary

The Department of Primary Industries and Regional Development’s (DPIRD) Statistical Seasonal Forecast (SSF) system is indicating less than 40% chance of exceeding median rainfall for November 2018 to January 2019 for the northern grainbelt and south-west corner and neutral (40-60%) chances elsewhere.

  • The SSF is indicating less than less than 40% chance of exceeding median rainfall for November 2018 to January 2019 for the northern grainbelt and south-west corner and neutral (40-60%) chances elsewhere. The most probable decile range is decile 2-3 for most of the grainbelt. Predictive skill based on October conditions is mostly poor to good (50-70% consistent).
  • The Bureau of Meteorology’s current seasonal outlook is indicating a 30-45% chance of exceeding median rainfall for November 2018 to January 2019 for the South West Land Division (SWLD). Predictive skill is mostly low to moderate (45-65% consistent).
  • Temperature outlooks for November 2018 to January 2019, from the Bureau indicate 75-80% chance of above average day-time maxima for the SWLD. Skill is moderate to high at 55-75% consistent. Minimum temperature outlooks indicate 65-75% chance of above average night-time minima for the SWLD, with skill mostly poor to high at 50-75% consistent.
  • October rainfall was average for the grainbelt. October maximum temperatures were average to above average and minimum temperatures were very much above average.
  • The combination of possible El Nino and positive IOD increases the risk of heatwaves and bushfire weather in the south, while there are typically fewer tropical cyclones in the Australian region.

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 the Seasonal Climate Information page.

For the next three months, November 2018 to January 2019, the SSF is indicating less than 40% chance of exceeding median rainfall for November 2018 to January 2019 for the northern grainbelt and south-west corner and neutral (40-60%) chances elsewhere. The most probable decile range is decile 2-3 for most of the grainbelt. Predictive skill based on October conditions is mostly poor to good (50-70% consistent).

SSF forecast of the probability of exceeding median rainfall for November 2018 to January 2019 using data up to and including October. Indicating a drier than normal outlook (less than a 40% chance) of receiving above median rainfall for northern grainb
SSF forecast of the probability of exceeding median rainfall for November 2018 to January 2019 using data up to and including October

Percent Consistent skill of the SSF at forecasting November to January rainfall using data up to and including October. Skill is 50 to 70 percent consistent.
Percent Consistent skill of the SSF at forecasting November to January rainfall using data up to and including October