Seasonal Climate Outlook Message for June to September 2004

The bottom line

Climate Watch 17th June 2004

While dropping in value since the start of the month the SOI has remained in positive values and as of the 16th June the 30day average is plus 5.4.

Based on the recent pattern of the SOI, there remains a reasonable 60-80% chance of getting at least the long term June to August median rainfall across a large part of southern Queensland. Rainfall probabilities are lower in the north west of the state though, with only a 30-40% chance of getting at least the long-term median rainfall through to the end of August.

For the rest of Queensland there is no strong signal at present towards wetter or drier than 'normal' conditions through to the end of August.

It will be very interesting to see if the SOI remains in positive values through to the end of the month. A drop back into negative values would give a slight fall in rainfall probabilities for the following 3months. However if the SOI where to remain in positive values there would be an improvement in the seasonal outlook across much of the state.

The late April/early May rain in many parts of Queensland was due, at least in part, to the Madden Julian Oscillation (MJO). The MJO is simply a band of low air pressure originating off the east coast of central Africa travelling eastward across the Indian Ocean and northern Australia roughly every 30 to 60 days.

Research has shown the MJO to be a useful indicator of the timing of potential rainfall events across much of Queensland. If its timing remains current, it would next be expected to have an influence on our weather over the next 5-10days.

Given the growing interest in the MJO, the DPI&F are in the process of developing an internet site that will allow anyone interested to track its passage. If you want to get access to this site let me know and I can e-mail you the details of it when the site is ready.

We are also offering a free 3month trial of a SMS text SOI update. A SMS message will be sent to your mobile twice a week (you can nominate days) and at the end of the month. If you are interested in receiving the SOI update or have any other climate related questions give me a call through the DPI&F Call Centre on 132523.