Australia weather: September marks second-hottest on record

The heat is on

Australia just wrapped up its second-hottest September since record-keeping began in 1910. According to Bureau of Meteorology data, the continent's minimum night-time temperatures were actually the highest ever recorded for September, narrowly beating the previous mark set in 2023. Real talk: average temperatures across the country were 2.71C above the long-term 1961–1990 average. If you're wondering when we had a cooler-than-average September, you'd have to look all the way back to 2004.

Winter is ghosting us

The most jarring stat comes from Kosciuszko National Park, where snow depth dropped to zero during the month. This is the first time that's happened in any September since monitoring started in 1954. Other alpine areas like Mount Buller, Falls Creek, and Mount Hotham also saw their hottest maximum temperatures on record. At Thredbo, the average night-time temperature stayed above freezing for the first time in 59 years. It’s giving major seasonal creep, where winter just decides to pack up and leave early.

How we got here

Climate scientists like Dr. Linden Ashcroft from the University of Melbourne are pointing to two main culprits: long-term global heating and a strengthening El Niño system in the tropical Pacific. This combo is creating a perfect storm for persistent high-pressure systems, which kept most of the country dry and warm. While Western Australia actually saw its second-wettest September since 1904, the rest of the states dealt with record-breaking heat and, for places like New South Wales and Victoria, some of the driest conditions on record.

Why it matters

With global heating pushing Australia’s average temps up by over 1.5C since 1910, these heat records are becoming the new normal rather than an outlier. The combination of an intensifying El Niño—forecast to be the strongest ever—and the long-term climate crisis means that weather patterns are shifting in ways that are hard to ignore. Ski resorts are closing early and the landscape is drying out, which is a massive L for the environment.