Southeast Australian temperature outlook

Issued 27 November 2013

Warmer summer days and nights more likely for New South Wales and Tasmania

Text details of chance of warmer maximum and minimum temperatures

Summary

  • Warmer days and nights are more likely over the eastern half of NSW and most of Tasmania
  • The odds for warmer or cooler days and nights are roughly equal across most SA, Victoria and western parts of NSW.
  • Climate influences include a neutral tropical Pacific, and local sea surface temperature patterns
  • Outlook accuracy for maximum and minimum temperatures is generally moderate over most of the eastern parts of Southeast Australia, with a few exceptions; see accuracy tab for more detail.
Probability of exceeding median maximum temperature, larger view Probability of exceeding median minimum temperature, larger view

Details

The chances of the summer maximum temperature exceeding the long-term median maximum temperature are greater than 60% over eastern NSW, most of Tasmania and coastal areas of SA (see map above). So for every ten summer outlooks with similar odds to these, about six or seven of them would be expected to be warmer than average over these areas, while about three or four years would be cooler.

Over most of SA, Victoria and western NSW the chances of receiving a cooler or warmer than normal summer are close to 50%, or roughly equal.

The chances that the average minimum temperature for summer will exceed the long-term median are greater than 60% over, the northeastern half of NSW, Tasmania and coastal parts of SA.

Climate influences

The tropical Pacific has remained ENSO-neutral since mid-2012. The dynamical seasonal outlook model indicates ENSO-neutral conditions will persist for the rest of 2013. This means the tropical Pacific Ocean is not producing a strong shift in the odds in this outlook.

With major climate influences likely to remain neutral over the coming months, secondary influences, such as the pattern of warmer-than-normal sea surface temperatures around the Australian continent are tending to drive the Australian climate.

How accurate is the outlook?

Outlook accuracy is related to how consistently the oceans and broadscale climate affect Australian temperatures. During summer, historical accuracy shows the outlook for maximum temperatures to be moderately consistent over most of NSW and eastern Victoria. Eastern SA, western NSW and western Victoria and most of Tasmania are only weakly consistent. Southwest SA, western Tasmania and central Victoria are very weakly consistent.

The effect on minimum temperatures during this season is moderately consistent over most of Southeast Australia, excluding parts of western Victoria, and Tasmania which are only weakly consistent.