Australia’s 2020 winter was the mildest winter in five years, with warm temperatures and low wind, according to the latest Australian Actuaries Climate Index.

The index, which measures the occurrence of extreme weather and sea levels, shows winter was relatively benign across most of Australia this year, sending the index down to levels not seen since 2015.

“The winter of 2020 is a reminder that despite a long-term trend of increasing temperatures and lower rainfall, thankfully not every season will see extreme weather,” Lead Collator Rade Musulin said.

Temperatures throughout the winter were more benign than the average of the 1981-2010 reference period. It marked the sixth-warmest winter on record, the Bureau of Meteorology says.

Only four out of 12 regions experienced extreme rainfall above the reference period average, while extreme wind conditions were below average for every region during winter.

Actuaries Institute President Hoa Bui says it remains critical that the Federal Government, businesses and communities continue to focus on risk mitigation as part of climate change preparedness.

The Royal Commission into National Natural Disaster Arrangements is due to report later this month, and the Institute expects recommendations to mitigate the future impacts of climate change.

Looking ahead, the Institute says the reprieve from wild weather may be short-lived. Above-average rainfall and a 66% chance of more tropical cyclones than average have been forecast by the Bureau of Meteorology as Australia moves into summer.

This is caused by the El Nino-Southern Oscillation (ENSO) weather system entering a La Niña phase in mid-September.

Past La Niña seasons have seen extreme events, including Cyclone Tracy in 1974 and the Queensland floods in 2010-2011.

The index, which was launched in November 2018, is updated every quarter and tracks changes in the frequency of extreme high and low temperatures, heavy precipitation, dry days, strong winds and changes in sea levels across 12 regions that are climatically similar.