Extreme heat that would have been extraordinary a decade ago is becoming routine. In late January 2026, south-eastern Australia experienced its most severe heatwave since 2019–20, with weather stations recording unprecedented temperatures. Port Augusta and Andamooka in South Australia hit 50.0°C on January 29–30, while Pooncarie in NSW reached 49.7°C. The entire region sustained dangerous heat between January 26 and 30, with the month's area-averaged temperature 1.90°C above the long-term average.
The impacts were immediate and measurable. Emergency hospital admissions in Melbourne surged by 25 per cent. The Australian Open suspended play on some courts and enacted its extreme heat policy. Across Victoria, bushfires spread rapidly under catastrophic conditions, with over 400,000 hectares of bushland and farmland burned. The Longwood fire alone consumed 137,000 hectares.
This is not an aberration. Australia's 2025 was the fourth-warmest year since observations began in 1910, with ocean temperatures at record levels for the second consecutive year. The long-term trend is unmistakable: the nation has warmed 1.59 degrees Celsius since 1910, with most warming occurring since 1950. Of Australia's 15 warmest years on record, 14 have occurred in the 21st century.
Climate science reveals how much human activity contributed to January's severity. According to the World Weather Attribution project, climate change made the heatwave 1.6 degrees Celsius hotter than it would have been in a pre-industrial climate. The event is now roughly five times more likely to occur than it would have been without human-caused warming.
The forecast offers little comfort. The Bureau of Meteorology predicts above-average temperatures throughout autumn (March to May 2026), with increased chances of unusual heat particularly early in the season. Warmer-than-average ocean temperatures off southern Australia suggest sustained heat stress ahead.
Australia's infrastructure and public health systems were designed for a different climate. As temperature records continue to fall and exceptional heat becomes routine, the nation faces a challenge that extends well beyond individual weather events. The January heatwave was severe partly due to timing and partly due to climate change. The structural question now is whether Australia's systems can adapt to a climate where 50-degree days are no longer rare outliers.