NSW Seasonal Rainfall Outlook: probabilities for Autumn 2004, issued 17th February 2004

Neutral autumn rainfall odds in NSW

The Bureau's autumn rainfall outlook for NSW shows no strong swings in the odds towards wetter or drier conditions. The outlook probabilities have arisen from the combined effects of above average temperatures in both the Pacific and Indian Oceans. However, these temperatures were not sufficiently extreme to produce a large shift in the chances of above median rainfall.

For the March to May period, the chances of above median rainfall are mainly between 45 and 60% across NSW (see map). So with climate patterns like the current, about 5 seasons out of 10 are expected to be drier than average over the State, with about 5 out of 10 being wetter.

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 autumn, history shows this influence to be weakly or very weakly consistent across most of NSW (see background information).

Both the Indian and tropical Pacific Oceans remain warmer than average, the former having a warming trend during January. For more detail see the the El Niño Wrap-Up.

The Southern Oscillation Index (SOI) has shown strong month-to-month variations recently, in association with active and inactive phases of the northern Australian monsoon. January's value was –12 which followed the +10 recorded in December. The approximate SOI for the 30 days ending 14th February was +3.

 

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 17th MARCH 2004.

Corresponding temperature outlook

January 2004 rainfall in historical perspective

November 2003 to January 2004 rainfall in historical perspective

 

Background Information