National Seasonal Rainfall Outlook: probabilities for Summer 2003/2004, issued 14th November 2003

Neutral odds for summer rainfall

The Bureau's summer rainfall outlook shows that above average seasonal falls are generally a 50:50 prospect in most parts of the country. The one exception is over an area of northeast Queensland where above average falls are the favoured outcome. This outlook is largely the result of recent temperature patterns and trends in the Indian Ocean.

For the December to February period, the chances of above median rainfall are between 60 and 65% over a region in northeast Queensland within about 300km of Townsville (see map). So with climate patterns like the current, about 6 seasons out of 10 are expected to be wetter than average in this part of the country, with about 4 out of 10 being drier.

probability of exceeding median rainfall - click on the map for a larger version of the map

In NSW, SA, the remainder of Queensland, the NT, Victoria, WA and Tasmania, the odds for above average summer rainfall are close to 50:50.

Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During summer, history shows this influence to be moderate across much of WA, some eastern areas in Queensland and NSW, parts of southern Victoria and the northwest of the NT. Across a large area running north-south through the centre of the country, the influence is mainly weak or very weak, as it is in Tasmania (see background information).

The tropical Indian Ocean has been cooling strongly over recent months and temperatures there are currently close to average. The Pacific on the other hand, is generally warmer than average, particularly in the west. For more detail see the El Niño Wrap-Up. The recent temperature changes in the Indian Ocean are the dominant influence on the overall pattern of probabilities.

October's value of the Southern Oscillation Index (SOI) was –2, the same as that recorded in September and August. The approximate SOI for the 30 days ending 11th November was –3.


Click on the map above for a larger version of the map. Use the reload/refresh button to ensure the latest forecast map is displayed.

The following climate meteorologists in the National Climate Centre can be contacted about this outlook: Grant Beard on (03) 9669 4527, Janita Pahalad on (03) 9669 4859, David Jones on (03) 9669 4085, Felicity Gamble on (03) 9669 4256.
Regional versions of this media release are available: | Qld | NSW | Vic | Tas | SA | WA | NT |

Regional commentary is available from the Climate and Consultancy Sections in the Bureau's Regional Offices:
Queensland -(07) 3239 8669 or (07) 3239 8666
New South Wales -(02) 9296 1522
Victoria -(03) 9669 4949
Tasmania -(03) 6221 2043
South Australia -(08) 8366 2664
Western Australia -(08) 9263 2222
The Northern Territory -(08) 8920 3813



Corresponding temperature outlook

October 2003 rainfall in historical perspective

August to October 2003 rainfall in historical perspective


Background Information