El Niño expected to develop in coming months, bringing hotter and drier weather to eastern Australia

BoM and other agencies expect transition to the first El Niño since spring 2023 sometime during winter

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Australia should prepare for an imminent El Niño, with the Bureau of Meteorology and other agencies forecasting that the weather phenomenon is likely to develop in the coming months.

“The models are really aligning now,” Felicity Gamble, a senior BoM climatologist, said. “We are expecting a transition to El Niño sometime during winter.”

The World Meteorological Organization said on Tuesday there was a 90% chance of an El Niño developing in the Pacific before November – a phenomenon that historically has increased the likelihood of hotter and drier conditions for Australia’s east.

El Niño is the warm phase of the El Niño-Southern Oscillation (Enso), one of the key drivers affecting global climate. During an El Niño, sea surface temperatures in a central region of the equatorial Pacific become warmer than average, resulting in a shift in atmospheric circulation.

As a result, there is less atmospheric moisture and heavy rainfall over the north of Australia, which shifts to the central and eastern parts of the Pacific.

“In order to really say that an [El Niño] event is established, we also need to see that response in the atmosphere as well,” Gamble said. “We are seeing signs of that, but we’re not quite there yet.”