SYDNEY – Flood-battered eastern Australia faces further extreme weather in the coming months after the country’s forecasters confirmed Tuesday that a “triple-dip” La Nina was under way in the Pacific.

A triple La Nina – in which the phenomenon spans three consecutive northern hemisphere winters, or southern hemisphere summers – has only occurred three times since the Bureau of Meteorology first started collecting records in 1900, most recently in 1998-2001.

The Bureau of Meteorology said the latest La Nina event, which brings intense downpours to Australia’s heavily populated east coast, would probably peak in spring with above-average rainfall expected to last through the southern hemisphere’s summer.

The country’s east is still recovering from intense storms and flooding earlier this year, which were caused by the previous La Nina event.

Hundreds of thousands of people had to be evacuated from their homes.

That event caused the city of Sydney’s wettest summer in 30 years, with meteorologist Ben Domensino describing the torrent of rain as an “atmospheric river”.

Ms Carlene York of the New South Wales state emergency services said Tuesday that there was a “very real possibility of flooding”, given rivers were still swollen and dams full.

“If you live in a flood-prone area, I urge you to take steps to prepare now,” she said.

La Nina is the large-scale cooling of surface temperatures in the central and eastern equatorial Pacific Ocean, normally occurring every two to seven years.

The effect has widespread impacts on weather around the world – typically the opposite impacts to the El Nino phenomenon, which has a warming influence on global temperatures.

Disaster responders in Australia’s east have been stretched thin by this year’s flooding, with New South Wales emergency services reporting its busiest ever year to June 30.

This even outstripped the need during the Black Summer bushfires, which burned through more than 24 million ha of the country’s east and engulfed major cities in smoke.

Australia is at the forefront of climate change, with scientists warning floods, bushfires, cyclones and droughts are becoming more frequent and more intense as the planet warms. AFP