National Seasonal Rainfall Outlook: probabilities for February to April 2005, issued 18th January 2005

Drier season more likely in north Queensland

There is a moderate shift in the odds towards below average rainfall for the late summer to mid-autumn quarter (Feb-Apr) in north Queensland, the Bureau of Meteorology announced today. Contrasting this, is an increase in the likelihood of wetter than average conditions in parts of western WA. But for most of the country, the chances of accumulating at least average rain between February and April are close to 50%.

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

For the February to April period, the chances of above median rainfall are between 30 and 40% in Queensland north of about St Lawrence (see map), which means that below median falls have a 60 to 70% chance of occurring. So in years with ocean patterns like the current, about six or seven seasons out of ten are expected to be drier than average in north Queensland, with about three or four out of ten being wetter. This outlook pattern is mostly due to above average temperatures in the tropical Pacific Ocean.

In parts of Western Australia near and to the northwest of Meekatharra, the odds favour above average falls for the coming season. The chances of exceeding the February to April median in this area are about 60%, which equates to about six years in every ten.

Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During the February to April period, history shows this influence to be moderately consistent through the northern halves of both Queensland and the NT, most of WA, the far west of SA and southeast NSW. Elsewhere the influence is only weakly or very weakly consistent (see background information).

Climate patterns across the Pacific continue to show some signs that are consistent with El Niño (eg warm central Pacific temperatures), and some that are not (eg wind and cloud patterns). The Southern Oscillation Index (SOI) was –8 in December following –9 in November. The approximate SOI for the 30 days ending 15th January was –3.

For routine updates 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 El Niño 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, Felicity Gamble on (03) 9669 4256, David Jones on (03) 9669 4085
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

December 2004 rainfall in historical perspective

October to December 2004 rainfall in historical perspective


Background Information