Atmospheric and oceanic indicators of the El Niño-Southern Oscillation (ENSO) generally continue within the neutral range. The recent increase in the Southern Oscillation Index (SOI) has been due to persistent high pressure weather systems in the central Pacific Ocean, and is not considered indicative of the broadscale climate. The SOI is known to be volatile at this time of year.
Summer ocean surface temperatures around Australia were the highest on record. Some cooling of the ocean off Australia’s northern coast has taken place in the last fortnight, in association with tropical cyclones Sandra and Rusty, but southern waters remain warm. High ocean temperatures may promote increased local rainfall in favourable weather conditions.
Climate models indicate the tropical Pacific is likely to remain ENSO-neutral through the first part of the southern hemisphere autumn. While it is known that predictions from dynamical models during the April through June period have lower skill, all models agree that an ENSO-neutral state is the most likely scenario for the next season.
The Indian Ocean Dipole (IOD) has little influence upon Australia’s climate from December through to April. >> More