Summary: El Niño continues to weaken

There has been a sustained cooling of the equatorial Pacific since early December, with current SST anomalies now close to their El Niño thresholds. This is the clearest sign that the El Niño event is weakening and it bodes well for a switch towards average or wetter than average conditions across eastern Australia sometime in the late summer or autumn. In fact, we've already seen a southward extension of tropical moisture which resulted in heavy rain over the NT, SA and the western parts of Queensland, NSW and Victoria. This can be taken as a sign that rainfall patterns are beginning to change across Australia, the timing of which is consistent with that observed during previous events.

In addition to the surface cooling, there has been substantial cooling below the surface; a situation that is likely to promote further weakening of the surface El Niño pattern. However, the SOI, Trade Winds and central-western Pacific cloudiness have seen their decline towards neutral values arrested somewhat during January, in association with a westerly wind burst mid-month. The westerly burst has now dissipated, so it is expected that these other ENSO indicators will continue their general trend towards neutrality over the coming months, in keeping with the weakening of the El Niño event. Furthermore, computer modelling supports the view that the El Niño will continue to decline.

Bom Update