I have been getting quite a few requests relating to the Autumn and Winter period and obviously Spring 2022 (just a wee bit too far out at the moment for Spring) so lets take a look at the early indications. This is preliminary data of weak signals from the climate drivers and thus you have to place a lot of what you see here in a low confidence bracket.

Anyone offering you high accuracy....well that is just not possible. Like a lot of people on the land, forecasting is like gambling and I am as conservative as they come and tell it like it is. This is a low confidence forecast based on statistics and where the drivers data is currently placed at the moment.

We need to see how the La Nina resolves in the ENSO region, we also need to get more information on the IOD impacts, some modelling suggesting a negative phase could develop but the trend is not overwhelming. However sometimes when you get a negative signal at this time of year, it usually leads to a negative event, not always, but more often than not.

Finally, the SAM is near impossible to predict more than a week out at times. This will be a huge influence to the cold weather impacts and how the rainfall and temperature forecasts do evolve through the season. The more negative the SAM, the higher chances of the westerly winds dominating the south of the nation with below average temperatures and frequent rain and snow. A more positive SAM, and you can have the negative IOD and the ENSO region neutral, under a persistent positive SAM, the east coast is wet and the south of the nation dry and mild.

Also, the SSTs need to be reviewed closely in the coming 2 months as we have warm waters surrounding the nation, more importantly in the Southern Ocean which is normal for the Austral Summer but will they persist into winter?

Lets take a look

*Remember the further you go out the less accurate the forecast is...not just here but any weather forecasting agency. The more hyperlocal you go the further out you go, the accuracy is even less!


Winter Rainfall Outlook 2022

% chance of exceeding or not exceeding the median seasonal rainfall expectations for Winter 2022

The shift in the SSTs around Australia during the Summer, especially through the Southern Ocean, the warming of waters over the Central Indian Ocean and the lingering La Nina helping to propel the warmer waters towards the east coast, all combining to keep the wet bias going over some parts of the nation. The wet season over the north should ease by May but there could be lingering rainfall for parts of the Top End and especially the eastern Top End and Cape York with the return of southeasterly winds, these could be heavier than normal. The east coast will have their wet season linger into June and then ease into July. Rainfall over the east could be heavier than normal under the current guidance, especially if the SAM remains more positive than not, in response to the lingering La Nina. As we move through the season, the westerly wind belt will be with us and how much of an impact that will have on rainfall is something that no one knows, that is determined by the SAM which you can only really accurately gauge 7-10 days out. At this stage the climate models are supportive of seasonal rainfall for most of southern Australia but areas exposed to the westerly wind belt, like Tasmania and western VIC and through southern SA and elevated areas of NSW and west of the ACT could see heavier falls. The Indian Ocean is likely to remain neutral through to about July or August at this time so little impact for now, but this driver may change further as we go through Autumn. Overall, no sharp dry signal at this time.

Winter Temperature Outlook

% chance of exceeding or not exceeding the median seasonal temperature expectations for Winter 2022

Seasonal values are anticipated for the nation's south and central areas, and most of the east coast. Northern Australia may see increased temperatures with the lingering humidity values, with above average nights and day times. Parts of southern Tasmania may be below average with extensive cloud cover and westerly winds with higher moisture content available leading to dreary days. The east coast should be cooler than normal in June but start to return to normal values in July through August as westerly winds take over from the wet easterly winds of Autumn. Otherwise most elsewhere, no real departure from average.

Key Points

Refer to the video for more information on the forecast charts and notes where I run through the data. This forecast will be looked at again during March.

More details to come on Winter with an outlook on some of the elements from snow, rainfall, temperatures, frost etc to come in the coming weeks.

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