El Nino declared – here's what it means for Australia’s forecast

It’s official: El Nino has arrived.

The Bureau of Meteorology today declared that the major climate driver was locked in across the tropical Pacific, with experts warning it could intensify into one of the strongest events in decades.

The news puts millions of Australians on notice for a warmer, drier winter and spring.

The changing conditions could spark earlier bushfires and heatwaves, while threatening water storage, farming yields, and snow depths.

Australians are being warned to brace for a potentially powerful climate cycle, with forecasters tracking an event likely to stick around well into the second half of 2026.

While it does not guarantee drought or extreme weather, the disruptive weather pattern can increase the odds of those conditions.

How we got here

The Bureau of Meteorology confirmed today that the El Nino–Southern Oscillation (ENSO) had entered an El Nino phase, ending months of speculation after warning signs first emerged in March.

The ENSO had been neutral since the generally wetter La Nina state ended in late March.

The El Nino climate driver, a natural warming of the tropical Pacific Ocean, often coincides with below-average winter and spring rainfall across central, southern and eastern Australia, although the bureau stressed no two events were identical.

Its latest long-range outlook suggests parts of southern and eastern Australia are likely to receive less rainfall than usual between July and September, while much of the country can expect above-average temperatures.

Below-average rainfall does not mean no rain, and individual weather events such as east coast lows could still bring heavy downpours.

Reading the signals

Most climate models indicate that El Nino is likely to become “strong” to “very strong”, although the bureau says the strength of an event does not always match its impact on Australia.

The last El Nino, in 2023-24, coincided with the nation’s driest August to October period on record but heavy east coast storms and tropical cyclones later delivered widespread summer rain.

The bureau noted that El Nino years were often linked to reduced winter and spring rainfall, hotter daytime temperatures across southern Australia, and an increased risk of frost due to clearer skies.

While a typical El Nino reduces rainfall across the eastern states and the interior during winter and spring, local weather is driven by a mix of climate factors, so actual conditions can vary.

The double-whammy risk

A neutral Indian Ocean Dipole is also being monitored, with forecasts suggesting it could turn positive during winter.

If that eventuates alongside the natural weather cycle, it can increase the chance of dry conditions across southern and eastern parts of the country.

As for summer, it’s too early to predict what will be on the cards, but El Nino can increase the risk of hotter days, heatwaves and bushfires in a warming climate.

Current forecasts suggest the event will persist through much of 2026 before weakening early next year.