|National Seasonal Rainfall Outlook: probabilities for April to June 2005, issued 18th March 2005|
Wetter season favoured in SE Qld and northern NSW
There is a moderate shift in the odds towards above average rainfall for the June quarter (April-June) in parts of eastern and northern NSW, and southeast Queensland, the Bureau of Meteorology announced today. For the rest of the country, the chances of accumulating at least average rain for the coming three months are close to 50%.
For the April to June period, the chances of above median rainfall are between 60 and 70% in an area roughly bounded by Nowra, Cobar, Charleville, Gladstone and the east coast (see map). So in years with ocean patterns like the current, about six or seven June quarters out of 10 are expected to be wetter than average in this region, with about three or four out of ten being drier.
Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During the June quarter, history shows this influence to be moderately consistent in a band from northwest WA across SA, the far southwest of NSW and over most of Victoria. Moderate consistency is also evident in southeast Queensland, northeast NSW, eastern Tasmania and patches in the NT. Elsewhere the influence is only weakly or very weakly consistent (see background information).
After reaching +2 in January, the Southern Oscillation Index (SOI) fell strongly in February to a value of 29, the lowest for any month since February 1983 (33). The approximate SOI for the 30 days ending 15th March was 20.
Recent low SOI values have caused some speculation regarding a possible El Niño developing in 2005. While the risk has increased it is too early at this stage to predict what might happen in the Pacific, with any confidence. For routine updates and comprehensive discussion on the latest data relating to El Niño, together with details on what the phenomenon is and how it has affected Australia in the past, see the ENSO Wrap-Up.
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|
Regional commentary is available from the Climate and Consultancy Sections in the Bureau's Regional Offices:
THE NEXT ISSUE OF THE SEASONAL OUTLOOK IS EXPECTED BY 15th APRIL 2005