Seasonal Climate Outlook Message for August to November 2002

The bottom line

Relief Rain Welcome 27/08/02

Welcome relief rain was recorded across many parts of Queensland over the previous fortnight. Generally speaking, the rainfall received has offered much needed relief to producers particularly in the drier areas of the south and south east of the state where some useful rainfall totals were recorded.

However the amounts received varied greatly depending on location. Further rain will be needed to produce any real lasting change in the dry seasonal conditions existing across much of the state.

An example of the dry conditions that have existed across much of the state is at Kingaroy. The long term average rainfall for January to August is 488mm. For the year to date (including the 98mm received in the 7 days to Tuesday 27th August) there has only been 241mm.

The recent rainfall events coincided with the passage of the 30-50day intra-seasonal oscillation (also know as the MJO). Regular readers of this column would be aware of the usefulness of the MJO in helping to predict the timing of rainfall over Queensland.

The MJO is simply a band of low atmospheric pressure that originates off the east coast of central Africa. It travels eastward across the Indian Ocean and northern Australia roughly every 30 to 50 days. While it is a tropical phenomenon, it appears to indicate the timing of potential rainfall events (but not indicate rainfall amounts) over central and southern Queensland.

The use of the MJO as a reliable forecast tool is still at the research/experimental stage. The Queensland Centre for Climate Applications and the Uni of Southern Queensland have a study project looking at the use of the MJO as reliable rainfall prediction tool for Queensland.

Given the recent rainfall activity, many producers will be waiting to see if the next passage of this phenomenon (around the last week of September/early in October) will help create some more relief rainfall across Queensland.

An updated outlook covering the period September to November will be released next week.

Last updated: 27 August 2002