|Tas Seasonal Rainfall Outlook: probabilities for October to December 2005, issued 15th September 2005|
Reduced falls for much of Tasmania
Seasonal rainfall odds released today by the Bureau of Meteorology, indicate an increased likelihood of below median falls over much of Tasmania for the December quarter (October to December).
For the October to December period, the chances of above median rainfall are between 30 and 40% across most of Tasmania, with the exception of the southwest and a small part of the east (see map).
So in years with ocean patterns like the current, about three or four December quarters out of ten are expected to be wetter than the median over much of Tasmania, with about six or seven out of ten being drier.
Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During the December quarter, history shows this influence to be moderately consistent over northwest and central Tasmania, but weakly consistent in the east and southwest (see background information).
The Southern Oscillation Index (SOI) fell from +1 in July to −7 in August. However, the SOI has begun to rise again with the approximate value for the 30 days ending 12th September being −1.
With all the main tropical Pacific climate indicators remaining neutral, an El Niño event developing in 2005 is not considered a realistic possibility. For routine updates and comprehensive discussion 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 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 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 Hobart Office: (03) 6221 2043.|
THE NEXT ISSUE OF THE SEASONAL OUTLOOK IS EXPECTED BY 18th OCTOBER 2005