La Niña, the weather pattern that has hit Australia with record rainfall and flooding for months, is finally over, according to the Bureau of Meteorology (BOM).
Key points:
- A climatologist says a third consecutive La Niña could increase the chances of rain for an “already saturated” east coast
- A La Niña triple has only happened three times before, the last in 1998-2001
- La Niña was associated with the devastating floods in NSW and Queensland earlier this year
But some models suggest that La Niña could be re-formed in the southern hemisphere during the spring for the third time in a row.
“As a result, the office’s ENSO prospect status has shifted to La Niña watch,” the BOM reported today in its climate controller update.
“La Niña ‘s clock means that there is about a 50% chance that La Niña will be formed later in 2022.
“That’s about twice the normal probability.”
BOM long-term forecast chief Andrew Watkins said a La Niña clock did not change the outlook for above-average rainfall for much of the country in the coming months.
“The office’s long-term outlook remains wetter than average, consistent with the outlook for the model of other global forecasting centers, reflecting a number of climate factors, including a negative Indian Ocean dipole (IOD ) developing and warmer-than-average waters around Australia, “said Drs. said Watkins.
“Sea surface temperatures are currently warmer than average on much of the Australian coast, especially in the north and west.
“This pattern is likely to increase the chances of above-average winter-spring rainfall for Australia.”
La Niña 2021-2022 is over, but there is a La Niña clock in its place. (Supplied by: Meteorological Office)
‘Already saturated’
A La Niña triple has only happened three times before, in 1954-57, 1973-76 and 1998-2001, according to climatologist Zoe Gillett of the ARC’s Center of Excellence for Extreme Climatics.
“A third La Niña in a row and could increase the chances of rain for an already saturated east coast,” he said.
This latest La Niña has been running since November 2021.
Since then, Eastern Australia has seen record rainfall and flooding, with Sydney experiencing the wettest year to date and the wettest fall in history.
“November 2021 was the wettest November in 122 years for New South Wales and Australia as a whole,” Dr Gillett said.
La Niña was associated with record floods that affected northern New South Wales and southern Queensland in late February and early March this year.
Fifty locations in southeast Queensland and northeast NSW recorded more than a meter of rain in the last week of February.
Much of eastern and western Australia recorded above-average rainfall this year, with parts of the NSW coast and parts of the Gold Coast Hinterland recording the wettest autumns ever recorded.
Posted 46 minutes ago, 46 minutes ago, Tuesday, June 21, 2022 at 7:46 AM, updated 13 minutes ago, 13 minutes ago, Tuesday, June 21, 2022 at 8:19 AM