THE 2020-21 La Nina event is now weakening, but it will continue to influence the weather patterns in Australia and the western Pacific for some time to come.
Most major climate models indicate the El Nino-Southern Oscillation (ENSO) will return to neutral during autumn, and it is favoured to stay neutral for most of 2021.
But, because of the continued influence from La Nina, above average rainfall is still more likely in many parts of eastern and northern Australia until late in autumn - albeit with a continuing degree of variability.
The neutral pattern after that will favour the occasional "one-off" rainfall event in the subsequent months, resulting in near-average rainfall throughout winter.
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But falls will be more patchy from region to region, and variable each month.
Across the Pacific, the cool waters in the eastern Pacific persist and a tongue of cooler water near the Equator has extended into the western Pacific.
Below that, around New Zealand and in the Coral and Tasman Seas, the sea surface temperatures (SSTs) remain above average - as they do around most of continental Australia as well.
Little change is expected in these SSTs in the coming month, and they will support a continuation of slightly above average temperatures during most of autumn at least. In fact, slightly above average temperatures are favoured for most months through 2021.
Above average temperatures in the tropical north east Indian Ocean seem to be persisting as well.
This feature will become increasingly important around April and May, as it is likely to contribute to a negative Indian Ocean Diploe (IOD).
A negative IOD is a positive for those looking for useful autumn and early winter rains in south eastern Australia.
Also, in the tropics, the pulse of the Madden-Julian Oscillation (MJO) is currently located over the central Pacific Ocean.
When the MJO is over the eastern Pacific at this time of the year, tropical areas across northern Australia often have a drier than normal spell and this is likely for the next couple of weeks.
Another pulse of the MJO is unlikely before mid-March, and that one could be the last of the season.
The Southern Annular Mode (SAM) is expected to stay neutral in coming weeks.
A neutral SAM at this time of year slightly reduces rainfall potential in the south of New South Wales, Victoria and Tasmania.
But, otherwise, it has little significant influence as other climate features dominate.
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