National Seasonal Rainfall Outlook: probabilities for May to July 2004, issued 19th April 2004

Generally neutral seasonal rainfall odds

The Bureau's seasonal rainfall outlook for the coming three months shows the chances of exceeding the median are close to 50:50 in most areas. The one exception is over a small region straddling the NSW/Queensland border where above average falls are more likely. This outlook pattern is a result of the combined effects of above average temperatures in both the Pacific and Indian Oceans.

For the May to July period, the chances of above median rainfall are between 60 and 65% in an area of the NSW/Queensland border near Moree and Goondiwindi (see map). So with climate patterns like the current, about six May to July periods out of ten are expected to be wetter than average in these parts, with about four out of ten being drier.

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

Across all the other States and Territories, and the remainder of NSW and Queensland, the chances of an above average May to July rainfall total are close to 50%.

Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During the May to July period, history shows this influence to be moderately consistent across most of Queensland, parts of north and east NSW, the central NT, Tasmania and in large patches across WA (see background information). Elsewhere the influence is only weakly or very weakly consistent.

Both the Indian and tropical Pacific Oceans remain warmer than average, although there has been a cooling trend in each. For more detail see the the El Niño Wrap-Up.

The Southern Oscillation Index (SOI) has shown strong month-to-month variations recently, in association with active and inactive phases of the northern Australian monsoon. March's value was zero following February's +9 and –12 in January. The approximate SOI for the 30 days ending 15th April was –20.


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, 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

March 2004 rainfall in historical perspective

January to March 2004 rainfall in historical perspective


Background Information