MELBOURNE, Australia — The El Niño–Southern Oscillation (ENSO) remains neutral, says the latest report from the Australian Government Bureau of Meteorology. However, the Bureau’s ENSO Outlook remains at El Niño WATCH, meaning there is approximately a 50% chance of El Niño developing during the southern hemisphere autumn or winter, twice the normal likelihood.
El Niño typically results in below average autumn and winter rainfall for southern and eastern Australia.
Tropical Pacific sea surface temperatures have warmed slightly in the past fortnight. In the sub-surface, weak warmth extends down to 175 m depth. Recent weakening of the trade winds in the western Pacific means that further warming of the equatorial Pacific is likely in the coming weeks to months.
Five of eight climate models indicate the central Pacific is likely to reach borderline or weak El Niño levels during autumn, with four models remaining above threshold levels into winter. El Niño predictions made in late summer and early autumn tend to have lower accuracy than predictions made at other times of the year. This means that current forecasts of the ENSO state beyond May should be used with some caution.
The Indian Ocean Dipole (IOD) is neutral. The IOD typically has little influence on Australian climate from December to April.