Seasonal Climate Outlook

Summary

The Department of Primary Industries and Regional Development’s (DPIRD) Statistical Seasonal Forecast (SSF) system is indicating less than a 40% chance of exceeding median rainfall for winter, June to August, and June to October 2018.

  • The SSF is indicating less than a 40% chance of exceeding median rainfall for the grainbelt for June to August 2018. The most probable decile range is decile 2-3 for most of the grainbelt. Predictive skill based on May conditions is mostly poor to good (50% to over 75% consistent). In operation since 2012, SSF has correctly indicated four out of six winter seasons in the northern, central and Esperance regions.
  • The Bureau of Meteorology’s current seasonal outlook is close to neutral, indicating a 40-50% chance of exceeding median rainfall for winter, June to August for the South West Land Division (SWLD). Predictive skill is mostly poor to moderate (50-65% consistent).
  • Temperature outlooks for winter, June to August, from the Bureau indicate a 60-80% chance of above normal day-time maxima for the SWLD. Skill is low to moderate at 45-65% consistent. Minimum temperature outlooks indicate a 55-80% chance of above normal night-time minima for the SWLD, with skill poor to good at 50-75% consistent.
  • For June to October, the SSF is also indicating less than a 40% chance of exceeding median rainfall for most of the grainbelt. As for winter, the most probable decile range is decile 2-3 for most of the grainbelt. Predictive skill is mostly poor to good, 50- over 75% consistent.
  • May rainfall was below to very much below average for the grainbelt, whilst the SWLD recorded it's second driest autumn (March to May) on record since comparable records commenced in 1900. May maximum temperatures were above average to very much above average in the SWLD, whilst May minimum temperatures were near average to below average.

Three month outlook for the South West Land Division

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 winter, June to August, the SSF is indicating less than a 40% chance of exceeding median rainfall for the grainbelt, with large parts having less than a 30% chance. The most probable decile range is decile 2-3 rainfall for most of the grainbelt. Predictive skill based on May conditions is poor to good (50-100% consistent). In operation since 2012, SSF has correctly indicated four out of six winter seasons in the northern, central and Esperance regions.

SSF forecast of the probability of exceeding median rainfall for June to August 2018. Indicating a drier than normal outlook (less than 40% chance) of receiving median rainfall for the grainbelt
SSF forecast of the probability of exceeding median rainfall for June to August 2018.

Percent Consistent skill of the SSF at forecasting June to August rainfall using data up to and including May. Skill is 50 to 100 percent consistent
Percent Consistent skill of the SSF at forecasting June to August rainfall using data up to and including May.

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