SA - SHOWERS CLEAR TODAY, WARMER WEEKEND, RAIN AND STRONG WINDS DEVELOP FROM THE WEST SUNDAY NIGHT.

ANALYSIS

A much more pleasant day across the state today, and there is more of that to come during Friday and into the first half of the weekend with high pressure nearby.


A strong front and low-pressure system skating through WA tonight and Friday will be the next wet weather system on the board that will begin to approach from Saturday. Ahead of it, a large cloud band is forecast to develop, and this will cover much of us by Sunday with a strong north wind.


Rain is not expected to reach the west until late Saturday and then the western Ag Areas during Sunday and the remainder from Sunday night into Monday, but as I have mentioned, the placement, timing and scale of the system is yet to be determined with poor guidance on the modelling.


SHORT TERM

That change has been tricky to pin down for a number of reasons outlined in the videos and the chat on here in the past few days and will continue to move around in the updates. Once we see that system on the satellite picture being analysed in real time, then the forecast confidence increases.


For now, increasing rainfall chances for areas across the state, with the highest rainfall chances forecast near a change moving passing through during the early part of the week.


The position of this system will then impact the systems following in the westerly wind belt following mid to late next week and also the development of the system over northern Australia with moisture spreading southwards. There have been rumblings for inland rainfall over the NT and QLD which may shift southwards into the eastern and southeast inland, but the confidence is poor.


LONG TERM

So that forms the longer-term forecast interest, do we see the rainfall over the north of the country spreading southwards or do we see the frontal weather win out with the negative SAM phase? That will be the question that remains unanswered for a few more days yet so be patient and any strengthening of the forecast confidence, and I will advise accordingly.


It does appear that the focus of the rainfall may be over the southeast with the frontal weather later next week into the following weekend and patchy to widespread rainfall possible over the northern and northeast areas of the state.


AREAS TO WATCH

Could also see some deepening moisture over in the west of the nation as well with the chance of a fairly vigorous cloud band forming towards the end of the month over WA which could traverse the nation into early July. It does come down to the system over the east and northeast and whether that develops or not later next week.


WEATHER VIDEO PM - THURSDAY 16TH JUNE 2022

FORECAST

Rainfall Next 10 Days

Rainfall looks to be confined to the system moving into the state from Saturday night with a burst of rain and strong winds for the Nullarbor but that will quickly dive southwards ahead of another strong front rearing northwards towards the state on Sunday. This will have a better chance of producing more widespread rainfall for the south of the state during Sunday night through Monday with the chance of more moderate rainfall if we see a broad low-pressure system develop in response to the slow-moving nature of the feature and colder air strengthening over the state. But the forecast confidence is poor. Widespread showers will continue to about this time next week. Another area to watch is what is happening over the NT, and if we see the northern aspect of the trough that passes through us early next week tap into deep moisture surging south from the Arafura Sea, then further widespread rainfall is possible over the north of the state.

Rainfall seasonal for much of the period, watching the potential for rainfall developing once again later next week with a developing cold front out of the Southern Ocean and the potential for rainfall breaking out over northern Australia that could come into the north of the state from next week with an upper trough, but confidence is low.

MEDIUM TERM

June 23rd-30th 2022

Rainfall Anomalies

Once again, low confidence in the forecasts into the end of the month and a lot of the rainfall forecasts are very low confidence for northern and eastern areas with the upper trough passing through. The rainfall over the south of the nation is at seasonal values with frontal weather passing through.

Temperature Anomalies

Cooler bias strengthening for parts of the eastern inland once again with a cold pool of air riding behind a cold front later next week then sitting over the eastern interior, continuing to buck the trend of climate models that were suggesting somewhat warmer conditions than what we have observed in the east. Seasonal temperatures out west but the warmer weather over the northwest will continue with dry air

DATA - Refer to the video for more information related to the charts above plus the daily breakdown through the short and medium term.


00Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 2 Weeks

More details can be found in the video however I am watching the two major systems of potential in the medium term, the event over northern Australia, where does that end up and the system that could come over WA at the end of the month with a major moisture infeed with above average rainfall.

00Z GFS - Precipitable Water Values - Next 2 Weeks

We are seeing that major rainfall event emerging through the medium term and clearly that has got a lot of people interested, but once again it is of low confidence and will be until early next week we will know more about that feature. For now, we are looking at the bulk of the wet weather found over southern parts of the nation via frontal weather.

00Z GFS - Rainfall Accumulation - Next 10 Days

Refer to the video for more context and analysis

00Z CMC - Rainfall Accumulation - Next 10 Days

Refer to the video for more context and analysis

00Z GFS - Rainfall Accumulation - Next 2 Weeks

Refer to the video for more context and analysis

A closer look in - I cannot add more caution to the wind with the rainfall over parts of the east through the medium term, so refer to the video for more information. For now the bulk of the rainfall is associated with the westerly wind regime over the southern parts of the nation, so coastal and adjacent inland areas of the south will see the best of it, and there may be a few showers over the east coast this weekend, possibly moderate about the extreme coastal fringe north of Sydney to Coffs.

More coming up from 8pm EST with a look at the models and rainfall.

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