Australia saw several power outages in different parts of the country due to increased use of air-conditioning, after temperatures regularly soared above 40° Celsius (103° Fahrenheit).
A government-linked climate group says more than 200 weather records have been broken during Australia's "Angry Summer."
Most of Australia's east coast endured its hottest summer on record, while torrential rain in Western Australia caused flash flooding.
The sort of unseasonable conditions seen between December 1 and February 28 will likely be recurring regularly in future, the group said.
The Climate Council report comes days after another independent report warned the impact of climate change had caused permanent damage to Australia's environment.
TRT World interviews climate scientist Will Steffen about Australia's erratic weather.