|Northern Aust Seasonal Rainfall Outlook: probabilities for April to June 2009, issued 24th March 2009|
Wetter period favoured for southeast Queensland
The northern Australian outlook for total June quarter rainfall (April-June), shows a wetter than normal season is favoured over southeast Queensland.
The pattern of seasonal rainfall odds across northern Australia is mainly a result of warm conditions in the Indian Ocean in February; the Pacific Ocean had little contribution to this forecast.
For the April to June period, the chance of exceeding median rainfall is between 60 and 70% over southeast Queensland (see map). This means that for every ten years with ocean patterns like the current, about six or seven years are expected to be wetter than average over this area, while about three or four years are expected to be drier.
New: Under the WATL part of the Bureau's website, there is an expanded set of seasonal rainfall outlook maps and tables, including the probabilities of seasonal rainfall exceeding given totals (e.g. 200 mm).
Across the remainder of the northern region, the chance of exceeding the median rainfall during the June quarter is between 40 and 60%, meaning that above median falls are about as equally likely as below median falls.
Outlook confidence is related to how consistently the Pacific and Indian Oceans affect Australian rainfall. During the June quarter, history shows this effect to be moderately consistent over southeast Queensland and patches in the NT. Elsewhere the effect is only weakly or very weakly consistent (see background information).
Pacific climate patterns were bordering on La Niña for several months, with above average wet season falls in the Australian tropics a direct result. The equatorial Pacific Ocean is warming and the consensus from computer models is for near average temperatures in the middle of the year. The SOI remains positive at approximately +3 for the 30 days ending 21 March. For routine updates and comprehensive discussion on any developments please 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. More detailed forecast maps, including the probabilities of seasonal rainfall exceeding given totals, can be found here.
More information on this outlook is available by contacting the Bureau's Climate Services sections in Queensland and the Northern Territory at the following numbers:
THE NEXT ISSUE OF THE SEASONAL OUTLOOK IS EXPECTED BY 24th April 2009