Seasonal Climate Outlook Message for August to November 2006

The bottom line

Climate Watch Dave McRae Qld DPI&F 14th August 06

The 30 day average of the SOI has trended downward from minus 8.6 at the end of July to minus 15.8 as of the 14th August. This has coincided with some strong westerly wind bursts in the equatorial region to the north east of Australia. At this time of year this is of some concern.

Although it is relatively late in the year for an El Nino to develop it will be worth watching sea surface temperatures and the SOI over the next few weeks. For example a Consistently Negative SOI phase at the end of the month would see a reduction in rainfall probabilities.

In the mean time there is a 40 to 50% chance of getting above median rainfall throughout most of Queensland for the August to October period. The exception is for the region running from the central Queensland coast to the peninsular where there is a low 20 to 40% chance of getting above median rainfall.

It is also worth noting that August and September have the lowest average monthly rainfall totals for most locations in Queensland.

Further analysis of historical rainfall data and the SOI indicates rainfall for Queensland during August to October is more likely to be close to median than well above median. Analysis of climate models or forecasts from other agencies (IRI, ECMWF, UK MET) also indicate that the chance of getting well above average or "drought breaking" rainfall is low.

Daily updates on the SOI are available on (07) 46881439. Rainfall probability maps are available at or For more information refer to Rainman StreamFlow or contact 132523 or (07) 3404 6999.

Last updated: 13 August 2006