Adelaide and other SA towns hit 40C before 10am as December record forecast to tumble in NSW

Widespread heatwaves leave residents sweltering across South Australia, Victoria and New South Wales

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Temperatures across South Australia soared past 40C before 10am on Monday as widespread heatwave conditions hit Adelaide and Melbourne and had parts of New South Wales bracing to endure their hottest December day on record.

Jonathan How, a senior meteorologist at the Bureau of Meteorology, said Adelaide had already reached its forecast maximum of 38C by 10am, after only dropping to 29.8 degrees overnight.

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