La Nina stubbornly delays collapsing | Western Magazine

The LA Nina weather event, which caused the wettest summer for parts of eastern Australia since 2010-2011, stubbornly refuses to dissipate.

After the Bureau of Meteorology reported the start of La Nina’s decay pattern last month, its latest update said the weakening process had halted, mostly due to strong trade winds.

The BOM now projects a return to neutral El Niño-Southern Oscillation (ENSO) conditions in late fall.

This could be good news for farmers in the Murray Darling Basin and southeastern parts of the country looking for a strong start to the fall growing season.

It will be a different story east of the Great Dividing Range, where much of the NSW coast and south-east Queensland has suffered significant flooding over the past month, where the likelihood of above-average rains average will probably not be welcome.

The BOM said weakening La Nina still has the potential to cause a sting in the tail, with tropical storm season officially continuing through April, which not only increases the potential for rain in the north, but also moisture being drawn south and producing heavy totals in southern regions. .

Strong trade winds cooled the water below the surface, halting the warming trend seen in January and February.

In the atmosphere, there is always a positive Southern Oscillation Index (SOI), correlated to La Nina.

In the near term, the BOM is monitoring an impulse from the Madden-Julian Oscillation (MJO), which is strengthening over the Indian Ocean. Most climate models suggest that the MJO is likely to move into the Western Maritime Continent region, centered over Indonesia, north of Australia in the coming week.

Generally, the BOM said that when the MJO is around Indonesia, there is an increased likelihood of cloudiness and above average rainfall in northern Australia and the islands to the north.

The risk of tropical cyclone development is also expected to be high in parts of northern Australia and the tropical southern Indian Ocean over the next fortnight.