The Bureau of Meteorology has announced an end to the 2021-22 La Nina in the tropical Pacific, with the status changed to La Nina WATCH.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
Whilst the 2021-22 La Nina has ended, there is around a 50 per cent chance of a La Nina event forming again during 2022.
Most of the observations and surveyed climate models of ocean temperatures and winds over the tropical Pacific Ocean indicate neutral El Nino-Southern Oscillation (ENSO) levels - neither La Nina nor El Nino are likely to persist during the southern hemisphere's winter.
The Bureau of Meteorology's head of long-range forecasting, Andrew Watkins, said the Bureau has been monitoring this trend of a weakening La Nina over several weeks.
"A La Nina WATCH does not change the outlook of above average rainfall for most of Australia over coming months," Dr Watkins said.
"The Bureau's long-range outlook remains wetter-than-average, consistent with model outlooks from other global forecast centres, reflecting a range of climate drivers including a developing negative Indian Ocean Dipole (IOD) and warmer-than-average waters around Australia.
"Sea surface temperatures are currently warmer than average for much of the Australian coastline, particularly to the north and west. This pattern is likely to increase the chance of above average winter-spring rainfall for Australia."
Currently, the IOD is neutral. But all climate model outlooks surveyed suggest a negative IOD is likely to form in the coming months.
Rainfall across eastern and southern Australia is typically above average during winter and spring during a negative IOD.
This year's La Nina event caused severe flooding across Northern NSW and South East Queensland devastating many farming districts and causing a delay in the sowing of winter crops and pastures. In some cases both crops and pastures had to be resown given the inundation that took place.
However in good news for irrigators in the Hunter Valley all three dams Glenbawn and Glennies Creek on the Hunter River system and Lostock on the Paterson River are at capacity.
This time last year (June 2021) Glenbawn storage volume at 441,158ML with 58.8% capacity Glennies Creek storage volume at 165,432ML with 58.2%. capacity and Lostock storage volume at 20,573GL with 102% capacity.
The change from the severe drought conditions of 2017-19 is clearly visible in these storage facilities and the impact of the big wet this year.
Full water allocations for irrigators are now guaranteed.