[AMENDMENT DUE TO TECHNICAL ERROR]

NSW Seasonal Rainfall Outlook: probabilities for January to March 2004, issued 16th December 2003

Neutral odds for March quarter rainfall in NSW

The Bureau's seasonal rainfall outlook for the March quarter shows no strong swings in the odds towards wetter or drier conditions in NSW. The chances of above average seasonal falls are generally close to a neutral 50%. This outlook is due to the fact that Pacific and Indian Ocean temperatures don't strongly influence Australian rainfall during mid-summer to early autumn.

For the January to March period, the chances of above median rainfall are between 40 and 55% across NSW (see map). So with climate patterns like the current, about 5 seasons out of 10 are expected to be wetter than average over the State, with about 5 out of 10 being drier.

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

Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During the March quarter, history shows this influence to be moderately consistent through approximately the eastern one-third of NSW, but weakly or very weakly consistent elsewhere across the State (see background information).

Following a recent cooling trend, the tropical Indian Ocean warmed slightly during November, as did the tropical Pacific. For more detail see the El Niño Wrap-Up. The temperature patterns in the Indian Ocean and Pacific Oceans are not extreme enough to produce large swings in the outlook probabilities.

November's value of the Southern Oscillation Index (SOI) was –3, slightly below the –2 recorded in October. The approximate SOI for the 30 days ending 14th December was +1.

 

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 (EDT) Monday to Friday by contacting the Climate and Consultancy section in the Bureau's Sydney Office: (02) 9296 1522.
 

THE NEXT ISSUE OF THE SEASONAL OUTLOOK IS EXPECTED BY 15th JANUARY 2004.

Corresponding temperature outlook

November 2003 rainfall in historical perspective

September to November 2003 rainfall in historical perspective

 

Background Information