Most of Sydney posted its hottest autumn, beating records set just two years earlier, with more than double the normal number of days exceeding 25 degrees during the season.

The Bureau of Meteorology said Australia as a whole posted its fourth-hottest autumn in more than a century of data, with maximums coming almost 1.75 degrees above the 1961-90 average.

NSW was the stand-out state, with average day-time temperatures beating the previous high – also set in 2016 – by a quarter of a degree. Maximum temperatures were 2.66 degrees warmer than normal.

Surfers made the most of the perfect autumn weather in Sydney at North Cronulla. Credit:John Veage

"All regions except Tasmania, Queensland, and the Northern Territory observed mean temperatures for the season amongst the ten warmest on record," the bureau said.