(Dated 12/06/02)
The 30day average of the SOI rose slightly over the last week and as of the 12th June was -13.8.
Despite this slight rise in SOI value the key point for the June to August remains the continuation of the low rainfall probabilities that have existed across Queensland this year.
Currently there is only a 20-50% chance of getting the median June to August rainfall for most of the south, west and far north coastal regions of the state. Across parts of central and north Queensland the probabilities vary between 30-70% depending on location.
The rainfall outlook for later this year will depend on just how the current SOI pattern continues to develop. If the SOI remains deeply negative through to the end of June we would expect quite low rainfall probability values to intensify and extend throughout eastern Australia. Also of interest is the latest United States Climate Prediction Centre (CPC) release, in which forecasters reported that the last passage of the 30-50 intra-seasonal oscillation (MJO) contributed to an increase in ocean surface temperatures. Ocean surface temperatures of 1 degree C above average were observed throughout most of the equatorial Pacific at the end of May. Most Nino indictors have also strengthened considerably. These include the increase in ocean temperatures, combined with observations of abnormally heavy rainfall in parts of South America and low rainfall over Indonesia.