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

Neutral outlook for NSW seasonal rainfall

Despite a shift in the odds towards below average rainfall in north Queensland, the chances of accumulating at least average rain for the late summer to mid-autumn quarter (Feb-Apr) are close to 50% in NSW, the Bureau of Meteorology announced today.

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 45 and 55% in NSW (see map). So in years with ocean patterns like the current, about five seasons out of ten are expected to be drier than average in New South Wales, with about five out of ten being wetter.

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 in parts of southeast NSW, but across most of the State 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.

More information on this outlook is available from 9.00am to 5.00pm (EST) Monday to Friday by contacting the Climate and Consultancy section in the Bureau's Sydney Office: (02) 9296 1522.


Corresponding temperature outlook

December 2004 rainfall in historical perspective

October to December 2004 rainfall in historical perspective


Background Information