Seasonal Climate Outlook Message for May to August 2006

The bottom line

Climate Watch Dave McRae Qld DPI&F 23/05/06 Currently sea surface temperatures in the central Pacific Ocean are in a neutral pattern. So while at this stage there does not seem to be any sign of an El Nino developing which is positive, it is noteworthy that Pacific Ocean sea surface temperatures are no longer reflecting the small La Nina pattern of the last few months. The output of the ocean or coupled ocean/atmosphere forecast models seems to reflect this as the majority indicate the continuation of a neutral sea surface temperature pattern. For more on conditions in the Pacific try the Bureau of Meteorology at www.bom.gov.au/climate/ahead/ In the mean time the 30day average of the SOI has experienced a downward trend since the start of the month to minus 0.3 as of the 23rd May. If this downward trend continues through to the end of the month there would be a drop in rainfall probabilities especially across the southern half of the state. As of the 22nd May the MJO was in Phase 1 (Africa) and would therefore be next expected across northern Australia around in early to mid June. The last two active phases of the MJO over north Australia occurred in relatively quick succession during late March/early April and then again in late April. The MJO is 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 (but not amounts). For more information try www.apsru.gov.au/mjo/ The latest rainfall probability maps are at www.dpi.qld.gov.au/climate or www.longpaddock.qld.gov.au and daily updates on the SOI are available on (07) 46881439. For more on rainfall probabilities, monthly medians or medians for your location refer to Rainman StreamFlow or contact 132523 or (07) 3404 6999.