Australia has recorded its second hottest September on record, with the Bureau of Meteorology confirming that the combination of global heating and a strengthening El Niño pushed temperatures to historic extremes across the continent.
The data revealed that minimum night-time temperatures were the hottest for any September since records began in 1910, a finding that underscores how climate change is reshaping temperature patterns even during the cooler months. Averaged temperatures ranked in the top five warmest Septembers for every Australian state, while the Northern Territory recorded its sixth hottest September.
The heat was not confined to urban or coastal areas. Alpine regions experienced record-breaking conditions, with snow depth recorded at zero in Kosciuszko National Park — a striking development for a month that traditionally marks the tail end of the southern hemisphere's snow season. The absence of snow cover in Australia's highest alpine environment signals significant stress on ecosystems and water systems that depend on seasonal snowmelt.
The Bureau of Meteorology's records, which stretch back more than a century, provide a long-term context for the anomaly. The fact that September 2026 ranked second only to one other year in overall heat, while setting an absolute record for minimum temperatures, suggests that the warming trend is intensifying in ways that affect both daytime and night-time conditions.
El Niño, a climate pattern characterised by warmer-than-average sea surface temperatures in the central and eastern Pacific Ocean, is known to amplify heat across Australia. When combined with the background warming driven by greenhouse gas emissions, the result is a compounding effect that makes record-breaking months increasingly likely.
Scientists have long warned that as global temperatures rise, the frequency and intensity of extreme heat events will increase. The September data adds to a growing body of evidence that Australia — already the driest inhabited continent — is particularly vulnerable to the effects of climate change.
The implications extend beyond temperature records. Warmer nights reduce the ability of ecosystems and agricultural systems to recover from daytime heat, increase energy demand for cooling, and can exacerbate health risks for vulnerable populations. The lack of snow in alpine areas affects tourism, water storage, and the survival of cold-adapted species.
The Bureau of Meteorology continues to monitor conditions as El Niño strengthens. With the summer months approaching in the southern hemisphere, the record September temperatures may signal a challenging season ahead for communities, farmers, and emergency services across the country.
The findings align with global observations that 2026 is on track to be among the warmest years ever measured, as the dual pressures of climate change and El Niño drive temperatures to new extremes worldwide.
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