Western Australian temperature outlook

Issued 28 May 2014

A warmer winter likely for Western Australia

Text details of chance of warmer maximum and minimum temperatures

Summary

  • Warmer winter days and nights more likely for WA
  • Climate influences include a warming tropical Pacific, and an easing of the warm eastern Indian Ocean
  • Outlook accuracy for maximum temperatures is moderate to high over the Kimberley, eastern Northern Interior, and west and south coast, with low to very low accuracy elsewhere
  • Minimum temperature accuracy is moderate over most of WA
Probability of exceeding median maximum temperature, larger view Probability of exceeding median minimum temperature, larger view

Details

The chances that the winter maximum temperature outlook will exceed the median maximum temperature is greater than 60% across WA, rising to greater than 80% in the Gascoyne and southwest (see map). So for every ten winter outlooks with similar odds to these, about six to eight winters would be warmer than average over these areas, while about two to four would be cooler.

The chances that the average minimum temperature for winter 2014 will exceed the long-term median are greater than 60% across WA, rising to greater than 80% over much of the southern half (see map).

Climate influences

The El Niño-Southern Oscillation (ENSO) is currently in a state of transition towards El Niño. Dynamical models surveyed by the Bureau indicate that further warming of the tropical Pacific is likely in the coming months, with most models approaching or exceeding El Niño thresholds during late winter.

Models indicate the currently warm tropical eastern Indian Ocean is likely to return to near normal. The Indian Ocean Dipole (IOD) is expected to remain neutral for the next three months, and is therefore unlikely to have a significant influence upon this outlook. However, the chance of a positive IOD is elevated during El Niño.

How accurate is the outlook?

Maximum temperature outlook accuracy for the winter period is:

  • Moderate to high over the Kimberley, eastern Northern Interior, and west and south coast
  • Low to very low
  • over much of WA

Minimum temperature outlook accuracy for the winter period is:

  • Moderate to high over most of WA