|Northern Aust Seasonal Rainfall Outlook: probabilities for November 2008 to January 2009, issued 28th October 2008|
Wetter than normal conditions favoured for most of northern Australia
The northern Australian outlook for rainfall over the early to mid-wet season period (November to January) shows a moderate shift in the odds favouring wetter than normal conditions over most of the NT and northern and western Queensland.
The pattern of seasonal rainfall odds across northern Australia is mainly a result of continued warmth in the central and southeastern Indian Ocean, especially off the west coast of WA.
The chance of exceeding median rainfall over northern Australia for the November to January period is between 60 and 70% for most of the NT and northern and western Queensland (see map). The odds rise to 70 to 75% in a few small areas over northern NT. This means that for every ten years with ocean patterns like the current, about six or seven years are expected to be wetter than average in these regions, while about three or four years are expected to be drier.
Across the rest of the northern Australia, the chance of exceeding the median rainfall for the November to January period is between 45 and 60%, meaning that above average falls are about as equally likely as below average falls in these regions.
Outlook confidence is related to how consistently the Pacific and Indian Oceans affect Australian rainfall. During the November to January period, history shows this effect to be moderately consistent across most of Queensland and the NT (see background information).
The tropical Pacific Ocean remains ENSO-neutral. Sea surface temperatures across most of the equatorial Pacific are near normal, however, sub-surface temperatures have recently cooled. The Southern Oscillation Index (SOI) is currently at +14 for the 30 days ending 25 October. Computer models indicate that neutral conditions are likely to continue for the rest of spring and summer. For routine updates and comprehensive discussion on any developments please 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 Monday to Friday from 9.00am to 5.00pm local time by contacting the Bureau's Climate Services sections in Queensland and the Northern Territory at the following numbers:
THE NEXT ISSUE OF THE SEASONAL OUTLOOK IS EXPECTED BY 26th November 2008