Another summer of heavy rainfall and humid, sticky nights is ahead for much of Australia as forecasters declare a rare third consecutive La Nina weather event.
The outlook for the rest of 2022 has been raised to an established La Nina, according to atmospheric and oceanic indicators, which inform the BOM’s La Nina alert system, the El Nino-Southern Oscillation (ENSO).
The BOM observed cooling in the central tropical Pacific Ocean in recent months, along with trade wind strength and equatorial cloudiness – all typical La Nina indicators.
It comes after months of reports of a likely third appearance of the weather pattern, which leads to heavier than usual rainfall, and cooler temperatures across the north and east coast.
La Nina conditions were blamed for devastating flooding in southeast Queensland and the NSW Northern Rivers this year.
“Models indicate this La Nina event may peak during the spring and return to neutral conditions early in 2023,” the BOM said.
Three consecutive years of La Nina is an unusual event, and has only occurred three times since 1900.
The statement added that climate change is continuing to influence climates locally and around the world, with Australia’s temperatures warming by about 1.47 degrees for the 1910-2020 period.
The country’s south has experienced an overall 10-20 per cent reduction in cool-season rainfall in recent decades.
There has also been a trend towards high-intensity rainfall events that occur over a short period of time, especially in northern Australia.
© AAP 2022