Australian livestock producers scrolling weather forecasts could be forgiven for confusion. There's plenty being said about how an El Niño will play out this spring. APlus News dove in the data to try to find some answers.
The short answer is that the major forecasters are looking at the same event and reaching similar conclusions on direction. Where they part ways is on the fine detail, and on how much history can be trusted to predict what happens next.
The BOM declared El Niño underway on June 16, 2026, and has been tracking its rapid intensification since. As of the week ending August 9, the Southern Oscillation Index sat at -25.6 over the prior 30 days, well past the -7 threshold used to confirm an El Niño pattern. July's monthly average of -29.1 was the most negative July value on record.
The Bureau's latest spring outlook, issued August 20, points to a split season. Rainfall is likely to be below average, with a 60% to greater than 80% chance, across the far southwest of Western Australia, southeastern Australia including Tasmania, and parts of eastern and northern Queensland, with parts of the southeast already carrying rainfall deficiencies from the past two years facing an increased chance of unusually low falls. Most of Western Australia, extending into the Northern Territory and western parts of South Australia and Queensland, is on track for above-average rainfall as the north transitions from the dry season into the wet.
The dry signal is strongest early in the season, with the wet signal in the west and north emerging from October, while southern Victoria and Tasmania stay drier than average right through. Daytime and overnight temperatures are likely to run above average across most of the country, with the strongest chance of unusually high temperatures across the southern two-thirds.
The BOM also notes a strong El Niño is now well established and continues to strengthen, with all models, including its own, pointing to further warming through spring and a peak as a very strong event in late spring or summer. A positive Indian Ocean Dipole remains in the wings too, with models suggesting it develops through the southern hemisphere winter and persists into spring, a combination that typically deepens the dry signal for southern and eastern cropping and grazing country.
It's worth noting that the exact figures quoted by different agencies this spring won't always line up, and that's not a red flag. NOAA, the Bureau and Japan's Meteorological Agency each use their own version of the Niño 3.4 measure, covering slightly different patches of ocean with different adjustments, so a like-for-like comparison isn't always straightforward. NOAA's Climate Prediction Center currently puts the chance of a very strong event this Northern Hemisphere fall and winter at greater than 90%. It's a minor bit of fine print behind the headline numbers, not evidence anyone's got it wrong.
Nutrien Ag Solutions Senior Science Fellow Eric Snodgrass has been more cautious than most about leaning on history to read this event, describing it as unlike anything on record. In his latest video update for Australia, Mr Snodgrass said ocean temperatures in the Niño 3.4 region have already reached 2.79°C above average, and could still climb past 4°C in that region, with readings as high as 5-7°C above average further east off South America. That would make it a strongly east-based event, rather than one centred in the middle of the Pacific.
He said the closest historical comparison is the powerful 1997 El Niño, though even that comparison is imperfect given how quickly the current event has developed and how much warmer the West Pacific and Indian Ocean are running compared with then.
Mr Snodgrass has also been tracking how poorly the standard El Niño data has performed against what has actually played out across Australia since April, with rainfall following a scattered pattern of wetter and drier patches that doesn't match the historical composite. That mismatch prompted him to build his own updated rainfall composites through mid-August.
Looking ahead, he expects spring temperatures to run above average nationally, in line with past El Niño years, which raises evaporation risk in areas already short on soil moisture. September is shaping up drier across most models, though several forecasts, including the Bureau's, point to a swing back toward near-average or wetter conditions through October, November and into summer, an unusual signal for an El Niño year.
Mr Snodgrass was upfront about the limits of any of this. "We do not know," he said. "We are simply trying to look at history, look at the models and the forecast, which suggests the future, and attempting to make some sort of statement."
"What I'm telling you is that this El Niño is not your typical beast. It's new, and we cannot ignore that."
He said the pattern has already shifted abruptly at short notice once this month, and cautioned that further swings, potentially lasting weeks, remain likely as the event continues to develop.
What is certain is that El Niño is constantly being talked about on social media, where forecasts, model snapshots and outright predictions circulate with little context on who produced them or when. At times it's worth asking whether the people posting believe what they're writing, or whether they're chasing clicks. What is becoming more common is farmers taking steps to pay for weather forecasts. Good weather data is imperative for the industry, but it remains in short supply. Whether the BOM's data proves useful this year is yet to be seen.
Being alert without being alarmed remains the sensible way to approach weather forecasting for your property. Getting an accurate picture now means checking more than one source rather than settling on the first forecast that lands in a feed, and knowing enough about each one to weigh up what it's actually saying.