Scorching October looms for two capital cities as temperatures soar to mid-30s

Queensland's capital is set to swelter under its hottest October day in years.

The temperature in Brisbane is forecast today to rise more than 9 degrees above the average for this time of year, as the mercury soars to 35 degrees.

Brisbane will be Australia's warmest capital city, while areas including Ipswich, Gympie and Logan will reach the mid-30s.

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Rockhampton is expected to push 39 degrees.

If today's temperature reaches 35 degrees, it will be the warmest October day for Brisbane since 2021.

Tomorrow and Saturday are forecast to be a little cooler, but temperatures will still in the high 20s.

Sydney is also facing a scorching start to October after its second-hottest September ever.

Last month was a month of extremes for the NSW capital, which endured its wettest September day in 146 years early in September, according to Weatherzone.

The weather reporting site also said the month as a whole was the second-warmest September siince 1858, when weather records began.

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Weatherzone said Sydney's average daily maximum temperature for the month was 23.5 degrees, 3.3 degrees above the long-term average, while its daily minimum was 13.1 degrees, about 1.9 degrees above the long-term average.

"Only September 2013 was warmer than September 2025 in Sydney for both maximums and minimums, while 2023 was slightly hotter than this year for maximums," Weatherzone wrote.

Temperatures in early October are set to continue the trend, with the mercury rising to 30 degrees on Sunday for the NRL and NRLW grand finals.

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The women's grand final, which will be played before the men's, will take place mid-afternoon, during likely oppressive heat.

Temperatures will drop early next week from that high, but will remain in the mid to high 20s, according to Bureau of Meteorology forecasts.

Weatherzone attributed the heat in recent weeks to both the overall warming climate and a sudden stratospheric warming over Antarctica.

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"The SSW is a weakening of the polar vortex which in turn leads to a negative Southern Annual Mode (SAM)," Weatherzone said.

"This tends to produce more frequent spells of warm, windy conditions on the NSW coast."

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