Queensland and the Northern Territory are on track for their warmest October on record against “every measure”, according to the Bureau of Meteorology.
Across the country it had been a “pretty unusual month”, a senior climatologist at the BoM, Hugh McDowell, said.
“It’s looking like it’s going to be the third warmest on record for the whole of Australia, and the warmest October on record by every measure for Queensland and the Northern Territory – that’s by maximum, minimum and mean temperatures,” he said.
Sydney and Brisbane were also headed for their hottest October in terms of maximum temperatures. “It’s not just the capitals,” McDowell said, with heat records likely to be widespread across New South Wales and Queensland.
Darwin airport experienced its hottest month on record, with maximum temperatures averaging 34.8C.
Sunday 19 October kicked off a week of extreme heat that saw records tumble from coast to coast.
NSW and Queensland recorded their hottest-ever October temperatures on 21 October, the highest since records began in 1910, according to the BoM.
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The remote outback village of Wanaaring in north-western NSW hit 44.9C – the state’s highest ever October temperature – a degree higher than the previous top of 43.9C set at Brewarrina on 31 October 1919.
Birdsville airport reached 46.1C, breaking the town’s previous October record for the whole of Queensland of 45.1C on 31 October 1995.
The drier and warmer conditions were influenced by persistent high pressure allowing heat to build up on land combined with more westerly winds linked to a negative Southern Annular Mode (a climate driver that affects wind and rainfall patterns), he said. “That’s all with a background of climate change.”
A contributing factor was the rare rise in stratospheric temperatures over Antarctica – called sudden stratospheric warming – that arose in September, and is now dissipating.
Sudden stratospheric warming events are usually associated with warmer and drier weather patterns, particularly for NSW and Victoria. There have only been three moderate to major events in the past 45 years – in 1988, 2002 and 2019 – according to the BoM, with the latter contributing to a worsening of the black summer bushfires.
Dr Martin Jucker, a senior lecturer in atmospheric science at the University of NSW, said the impact of the stratospheric warming event on rainfall was visible, particularly in NSW.
Rainfall and soil moisture for October was below average for much of the state, despite the wet start to the year.
“It’s interesting how it was always wet, wet, wet, wet, wet, wet. And then as soon as the sudden warming happened, it started getting less wet, and then suddenly neutral. And now we see October was actually drier in the south-east.”
Jucker, who is based in NSW, said weather-wise it had been “a horrible year” for the state.
“There’s been floods all over the place. There’s been some really strong rainfall events,” he said. “It had everything in it, but it also had the warmest day on record in October.”
The above average conditions were expected to continue, according to the BoM’s latest outlook, with daytime and night-time temperatures from November to January remaining above average for most of Australia.
Sea surface temperatures have been the warmest or second warmest on record every month since July 2024, and are forecast to remain above average.
Warmer oceans can provide increased moisture and energy that can enhance the severity of storms, cyclones and rain systems, according to the BoM.
Australia’s national annual average temperature is about 1.5C higher than in 1910, according to the BoM, and the climate crisis has increased the frequency and severity of extreme weather events.
