Apr 28, 2015
ENSO indicators in the tropical Pacific are approaching El Niño levels. Sea surface temperatures now exceed El Niño thresholds and trade winds have remained weaker than average for several weeks. This suggests some coupling between the ocean and atmosphere may be occurring. If these patterns persist or strengthen, El Niño will become established.
All international climate models surveyed by the Bureau indicate that ocean temperatures are likely to remain above El Niño thresholds until at least the southern hemisphere spring. However, the accuracy of model outlooks at this time of year, the traditional El Niño–Southern Oscillation (ENSO) transition period, is lower than at other times.
Based upon model outlooks and current observations, the Bureau's ENSO Tracker is at ALERT status. This indicates that there is triple the normal chance of El Niño in 2015. El Niño is often associated with below-average winter and spring rainfall over eastern Australia, and above-average daytime temperatures over the southern half of the country.
The Indian Ocean Dipole (IOD) remains neutral and model outlooks indicate a neutral IOD for the coming months. From May to November, the IOD can impact Australian climate. However, the Indian Ocean remains much warmer than average, which is currently influencing the Australian rainfall outlook, with an increased chance of above-average rainfall in the near term.
courtesy to
http://www.bom.gov.au/climate/enso/