Weather records have been smashed in the Illawarra, with Bellambi and Albion Park recording their hottest September days in 25 years.
And it's expected to continue on Tuesday and Wednesday, with a top of 33 degrees predicted before a southerly change blows in on Thursday drops the temperature down to around 18 degrees.
While there will be a total fire ban in place on the Far South Coast and Greater Sydney on Tuesday, the official rating for the Illawarra-Shoalhaven region is high.
The temperature raced to 34.7 degrees in Albion Park on Monday, September 18. It's the hottest day in 24 years for the suburb.
Also, the suburb has never recorded three days of 30-degree-plus temperatures since its weather station was installed in 1998.
It was a similar story in Bellambi, when the mercury reached 33.3 degrees, making it the hottest September day in 25 years.
"There's been four days of 30-degree-plus weather, it's a record for Bellambi since 1997," Weatherzone meteorologist Angus Konta said.
"It's been a very hot few days."
The very hot weather is due to a long trough across southern Australia that's dragging hot air towards the Illawarra.
"I wouldn't be surprised if we saw more records fall," Mr Konta said.
It's also been hot in Kiama, with a top temperature of 32.5 degrees on Saturday, this is around 12 degrees hotter than the average September day.
No records were broken however, with Kiama's hottest day in 2014, when it reached 33.4 degrees.
The Bureau of Meteorology warns severe heatwaves can be dangerous for many people.
"Especially older people, babies, children, pregnant and breastfeeding women, people with medical conditions and people who are unwell," the warning stated.
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