THE IMPACTS OF THE INDIAN OCEAN THIS YEAR.

For those that are waiting for rainfall and needing to repair their water table after a very dry period (this is for areas such as the Murraylands, Riverlands and Mallee areas for example), rainfall numbers and chances are likely to increase dramatically as we go through our spring.


I have spoken about the Indian Ocean multiple times - here and here and here so I won't bang on too much other than to mention for those who are using the land and preparing for the remainder of winter and spring, the rainfall frequency and intensity will increase through this year.


The Indian Ocean Impacts - For the remainder of the year. It is a general guide and not a rule of thumb, but based on current guidance this seems to be fair.

Blue Zones - High Impact from a negative IOD event.


This area can expect to see above average rainfall chances through July onwards to the end of the year, that's based off the current guidance from the climate models and other data sets I have scoured through in recent days. I am of the belief that the further we go into July, the wetter the phase will get likely to increase through August and September.


Flooding becomes a risk through parts of NSW, VIC and SA with the frequency of the rainfall and the intensity increasing as the nation warms up adding more atmospheric dynamics. That will see the rain become more thundery as well in line with the storm season, so the risk of not only riverine flooding, but flash flooding becomes an issue.


I will be talking more about the flood risks over the coming week for inland areas of QLD, NSW, VIC and SA because this could be on those situations where many who don't get the information could be caught with the pants down around their ankles what the hell is going on.


Light Green Zones - Moderate impact from negative IOD event.


Rainfall has a higher chance of being more frequent and heavy, but the risk of exceeding the average is not as elevated for July (though I have drawn in a wet bias in the latest climate outlook) Generally the rainfall is connected to the westerly wind belt and there are signs that will be present through early July with rainfall for a number of days for the region.


Longer term, the rainfall can be heavier through these regions but generally the above average rainfall risk is slight decreased off climate history. But with the IOD event continues into the late spring and summer, we could see rainfall continue through to the end of the year for interior regions where flooding may develop.


With early onset rainfall further moisture will likely pool from the north and northeast over these regions, not just connected to the Indian Ocean. That is more likely for central and eastern interior regions.


And in the east, an active and very wet storm season is likely to unfold, with not necessarily more severe thunderstorm events, but if forms form, thunderstorms may be more productive and lead to flash flooding events.


Dark green zones - Moderate impact from a negative IOD event.


High chance of more humidity values interrupting the dry season over the coming months with significant chances of pop up showers and storms through the dry season from time to time between July to August.


The build up likely to be earlier through the NT and Cape York and then spreading into the Kimberly. The build up likely to start with a protracted period of higher humidity and not much rainfall then a more active storm season from October through November.


Early onset rainfall is highly likely for large areas (I will have more to say about this is a couple of weeks). This may suppress day time heat indices which are excessive during this period.


The IOD lingering into early summer could elevate the risk of early cyclones over the Indian Ocean in particular ahead of the monsoon developing later in December.


Rainfall looks likely to be above average from October through December through these regions.


The take away?


The rainfall frequency looks to persist into December as well, and then there is the talk of La Nina possibly developing which I am not going to discuss other than saying, yes some models are indicating this


ENSO Forecast for the end of the year - BoM model


With wet catchments in place for many locations over the eastern inland, it is primed and ready for a flood events through spring under current climate guidance. So keep up to date, spread the word to your colleagues, get this subscription! It could be useful and a cheap investment.


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Need more weather information? A climate forecast for your property once a month can be just what you need to give you the edge - email karllijnders@weathermatters.org for more details.



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