|Tas Seasonal Rainfall Outlook: probabilities for April to June 2005, issued 18th March 2005|
Neutral outlook for Tasmanian seasonal rainfall
There are no strong shifts in the odds towards either above or below average rainfall for the June quarter (April-June) in Tasmania, the Bureau of Meteorology announced today.
For the April to June period, the chances of above median rainfall are mainly between 50 and 55% across the State (see map). So in years with ocean patterns like the current, about five June quarters out of 10 are expected to be wetter than average over Tasmania, with about five out of ten being drier.
Outlook confidence is related to the influence of Pacific and Indian Ocean temperatures on seasonal rainfall. During the June quarter, history shows this influence to be moderately consistent across the eastern half of Tasmania, but only weakly consistent in the west(see background information).
After reaching +2 in January, the Southern Oscillation Index (SOI) fell strongly in February to a value of 29, the lowest for any month since February 1983 (33). The approximate SOI for the 30 days ending 15th March was 20.
Recent low SOI values have caused some speculation regarding a possible El Niño developing in 2005. While the risk has increased it is too early at this stage to predict what might happen in the Pacific, with any confidence. 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 15th APRIL 2005