Major change to weather outlook for Aussie summer as La Niña chances recede
While a wet La Niña event is still a possibility, if it does materialise it could be 'weak and short-lived', a BoM climatologist told Yahoo.
Initial fears that millions of us will be drudging our way through yet another very wet summer may have been a bit premature, with expert meteorologists saying the outlook appears to be changing.
Earlier indications that Australia was in for a fourth La Niña weather event in just five years were first raised in May, however the Bureau of Meteorology announced this week that such an outcome is looking increasingly unlikely. Despite some indications a La Niña was on the horizon over recent months, sea surface temperatures are remaining neutral, the BoM states in its latest weather outlook.
“When we say the El Niño–Southern Oscillation (ENSO) is neutral, it means that there’s no active El Niño or La Niña occurring right now,” BoM climatologist Zhi-Weng Chua told Yahoo News Australia.
While there are still “some signs that a La Niña may develop”, with one model suggesting the Pacific will cross the threshold from late spring to early summer, Mr Chua said “it’s not a guarantee”.
“The chance of an event developing this year is a bit lower than what we assessed in early spring or even the middle of spring.”
So the chances of millions of Aussies along the east coast experiencing rainfall significantly above the average appear to be lessening by the day.
Possible La Niña could be 'weak and short-lived'
According to the BoM’s outlook, if a La Niña does eventually develop it may “be weak and short-lived”. However, Mr Chua did say that is not always the case.
“I think in terms of impacts, when they look at the strength of rainfall impacts with the sea surface temperature anomaly of La Niña events, there is some relationship or correlation, but it can every event can be different,” he said.
“So even with a weak event, you still could see some significant rainfall impacts even though there generally is a relationship between the rainfall impact and the strength of the anomaly.”
Australia to see above-average temperatures
Models forecast conditions will stay neutral until March, Mr Chua explained. The prediction, along with other influences, suggest most of Australia will “very likely” see above average temperatures over the coming months.
“In terms of rainfall, it’s looking likely to be above average for parts of eastern Australia and Western Australia but it’s important to note that this kind of long range forecast for summer, it can evolve over time, and we expect the accuracy to increase as we get closer,” the climatologist said.
If La Nina or a brief -IOD do not form by year's end, than 2024 will become the first year in a decade without a major climate driver pic.twitter.com/8e0wjfpcio
— Thomas Saunders (@TomSaundersABC) October 21, 2024
For most of central Australia, western Victoria and southern WA, wet weather is expected to be typical for the season.
Do you have a story tip? Email: newsroomau@yahoonews.com.
You can also follow us on Facebook, Instagram, TikTok, Twitter and YouTube.