The potential for flooding remains moderate over the southeast and eastern inland of the nation in addition to the flooding that is underway and peaking through the Central West of NSW. But before then, the weather is expected to turn wet over southern WA first before it spreads through to SA later Friday and then into VIC and NSW this weekend.

Thunderstorms will be featuring throughout the latter part of this week into the weekend with those storms potentially leading to heavy rainfall and flash flooding.

Storms may also develop over southern QLD during Sunday with the trough passing through NSW, and some of these could be severe with damaging winds and heavy rainfall leading to flash flooding.

For the northern tropics, the humid and unsettled weather is likely to return from later this week into the weekend with some of those possibly severe. The weather then turns traditional and seasonal as we track throughout the end of the month.

A secondary system is expected to develop over inland areas of the nation and from where that system goes will determine the spread of rainfall, which looks to be heavy. At this stage the eastern inland of the nation needs to pay attention to it. This could combine with a deep moist onshore flow to produce widespread rain and thunderstorms for the eastern parts of NSW and QLD.

Otherwise the wet signal develops for the west and central areas of nation as well, with moisture streaming out of the tropics.

Lets take a look


Rainfall Next 10 Days

Rainfall is expected to become more widespread this week, today being the last mainly dry day for most of the nation. As we track into the latter part of the week, the weather is expected to turn more unsettled with widespread rainfall and thunderstorms developing over southern and eastern areas of the nation with moderate to heavy falls from SA through VIC Friday and Saturday and into NSW on Sunday with thunderstorms about. Another system is expected to emerge out of the central areas of the nation with that feature still poorly modelled at the moment. Tropical weather is expected to increase with showers and thunderstorms developing. The moisture out of the northwest Indian Ocean may start to feed a trough over the western interior bringing more showers and storms later in the period.

Thunderstorm Forecast Wednesday

Thunderstorms are expected to be rather isolated nationally, perhaps tending scattered over the eastern areas of WA with gusty winds the main risk.

Flood Risk This Weekend

The heavy rainfall over VIC and NSW may lead to additional flood risks for parts of both states, with this area becoming more defined as the data off the models becomes clearer.


12Z Euro Surface Pressure Pattern and Rainfall Distribution - Next 10 Days

There are two systems as mentioned in the video with the first feature coming through in two parts, the first part weak. That will bring cloud and patchy rainfall from southern WA into SA and then the eastern states during Thursday. The tail of this system may bring a few storms to southeast and eastern NSW on Friday. The second part deepens over southern WA during Friday with areas of rain developing, with it spreading eastwards. The low deepens further over SA with a band of rainfall along and to the south of this system. The areas of rain then sweep into VIC and southern NSW during the weekend with locally heavy falls and further thunderstorms. The weather over the west stays dry this weekend with high pressure ridging in. Over the tropics the thunderstorms return from later this week and over the weekend with strong storms with heavy falls and gusty winds possible. Now the system moves on by during early next week off the NSW coast. Drier weather to start the week but a new low develops over Central Australia and this pulls in moisture over the eastern states with rain and thunderstorms developing, but model consistency is poor at the moment on this feature. The west however, with the high moving east mid to late next week, could see the warmest weather so far this Spring.

12z Euro Precipitable Water Anomalies - Next 10 Days

The higher than normal moisture content connected to the waning IOD continues to drive the rainfall chances up for southern and eastern Australia. There are two surges of moisture passing through this period. The first surge comes through southern WA into SA and then VIC and southern NSW. The secondary surge may come through central and eastern Australia mainly for the NT, northern SA and NSW and southern QLD.

12z Euro Precipitable Water Values - Next 10 Days

Moisture content is quite high with the lead system, being fed in from the Indian Ocean with that translating to widespread rainfall and cloud cover. But it is not until the moisture gets over the eastern states you see the moisture profile open up and this leading to more widespread rainfall with a low pressure system deepening.

12z Euro Rainfall Accumulation - Next 10 days

The Euro has been fairly consisitent but I will point out that if you are living in SA, that where the band sets up from northwest to southeast with the passage of the low pressure, that will determine the heaviest of the rainfall. It is a narrow band as you can see so some areas will see light rainfall but 50km north could see a month's worth of rainfall. The rainfall is more widespread over eastern VIC and through southern NSW. A follow up system is expected but that is also being poorly modelled.

12z GFS Rainfall Accumulation - Next 10 days

Poor consistency from run to run means that this carries a very low confidence.

12z CMC Rainfall Accumulation - Next 10 days

This has been the most consistent in terms of modelling this week with the Euro. The GFS has been volatile and carries a low confidence forecast strap due to this.

I will have a look at the tropical outlook for northern Australia today and how that will impact weather moving into December and the ENSO Update is due today as well plus your medium term forecast and much more! There is plenty of weather coming our way nation wide, regardless of what the modelling is doing from run to run!

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