MELBOURNE, Australia – The tropical Pacific Ocean remains neutral with respect to the El Niño–Southern Oscillation (ENSO), reports the Australian Government Bureau of Meteorology in its new Wrap-Up. Indicators including the Southern Oscillation Index (SOI), trade winds, cloudiness near the Date Line, and sea surface and sub-surface temperatures in the tropical Pacific are all at neutral ENSO levels.
Some warmer than average tropical surface waters, near to and west of the Date Line, are generating persistent cloudiness in the region. This pattern in the western Pacific may be reducing the impact of anomalously warm local sea surface temperatures around northern Australia, which would typically tend to increase rainfall.
Climate models surveyed by the Bureau indicate that ENSO is likely to stay neutral until at least mid-year, meaning it will have limited influence on Australian and global climate in the coming months. However, ENSO predictions made during autumn tend to have lower accuracy than predictions made at other times of the year. This means that current ENSO forecasts 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.
The Southern Annular Mode (SAM) is also currently neutral and is forecast to remain neutral for the next three weeks. The SAM has little influence upon Australian rainfall in autumn.