Seasonal Climate Outlook

Summary

The Department of Primary Industries and Regional Development’s (DPIRD) Statistical Seasonal Forecast (SSF) system for autumn, March to May 2019, is indicating mixed chances of exceeding median rainfall for the South West Land Division (SWLD).

  • For autumn, March to May 2019, the SSF is indicating less than a 40% chance of exceeding median rainfall for parts of the northern and central grainbelt, with greater chances (above 60%) for the far eastern grainbelt, South Coast and Esperance shires and neutral chances elsewhere. Most probable decile range is decile 2-3 for central and far northern grainbelt, decile 8-10 for eastern grainbelt, Ravensthorpe and Esperance shires and decile 4-7 elsewhere. Predictive skill based on February conditions is mostly poor to good (50 -70% consistent). 
  • The Bureau of Meteorology’s current seasonal outlook is indicating a neutral (45-60%) chance of exceeding median rainfall for March to May 2019 for the SWLD. Predictive skill is poor to moderate (45-65% consistent). 
  • Temperature outlooks for March to May 2019, from the Bureau indicate an over 80% chance of above average day-time maxima for the SWLD. Skill is mostly low to moderate at 45-65% consistent. Minimum temperature outlooks indicate greater than an 80% chance of above average night-time minima for the SWLD, with skill mostly poor at 45-55% consistent. 
  • February rainfall was generally below average in the SWLD. February maximum temperatures were above average and minimum temperatures were generally average. 
  • For seasonal forecasting, autumn is the 'predictability barrier', meaning the major climate drivers of El Niño/Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) are inactive. Therefore, seasonal forecasts have the lowest skill at this time of the year.

Three month seasonal forecast 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 web page.

For autumn, March to May 2019, the SSF is indicating less than a 40% chance of exceeding median rainfall for parts of the northern and central grainbelt, with greater chances (above 60%) for the far eastern grainbelt, South Coast and Espererance shire. Neutral chances are for the reaminer of the SWLD. The most probable decile range is decile 2-3 for the central and far northern grainbelt, decile 8-10 for eastern grainbelt and Ravensthorpe and Esperance shires and decile 4-7 elsewhere. Predictive skill based on February conditions is mostly poor to good (50 -70% consistent).

SSF forecast of the probability of exceeding median rainfall for autumn, March to May 2019, using data up to and including February. Indicating mixed chances of the Southwest Land Division receiving above median rainfall.
SSF forecast of the probability of exceeding median rainfall for autumn, March to May 2019, using data up to and including February
Percent Consistent skill of the SSF at forecasting March to May rainfall using data up to and including February. Skill is 50 to 70 percent consistent.
Percent Consistent skill of the SSF at forecasting March to May rainfall using data up to and including February