Pockets of severe weather ongoing with areas of flooding through Central and Northern NSW this morning with areas of heavy rainfall and flash flooding possible for Southeast, Riverina and the ACT as this complex low continues to slowly move east.

Some areas have well and truly broken November rainfall records overnight and there is more to come, putting a lot of pressure on already saturated river systems.

Gale force winds on the southern side of the side of the low through VIC and the ACT and pockets of Southeast NSW will continue today before easing tonight, significant tree damage is possible given how much rain has fallen.

For the remainder of the nation, it is seasonal and routine weather. The tropics copped a battering during the afternoon convection, with some locations recording 100mm/hr with high end flash flooding.

Lets take a look


Rainfall Next 10 Days

The rainfall continues to be widespread today and this will be the most widespread day of rainfall for the next week nationally. The low pressure system will begin to move offshore the southeast of NSW and the upper feature will remain over NSW driving further showers and a few storms Saturday and Sunday, extending into QLD. The wet weather will ramp up next week with this upper trough and the position and depth of moisture will determine the scale and spread of the rainfall through the eastern inland. That will become clearer by Saturday afternoon. The tropics looking wet and unsettled, with some of the heaviest rainfall seen so far this wet season to be replicated again throughout this period. The west on the other hand through to SA will be dry and settled with a ridge close by, but that high will move south and moisture will return by the end of the period.

Thunderstorm Forecast Friday

Thunderstorms are ongoing from overnight and they have packed a punch with flash flooding, damaging winds and even some large hail through the Upper Western of NSW and Southwest QLD. The focus of storms shifts east today north and east of the low. It is a cool and breezy rain mess now for southern NSW and the ACT. The storms back once again for the tropics with some heavy falls possible today. The storms over QLD could produce damaging winds and heavy rainfall leading to flash flooding once again.

DATA - Check out the GFS in the video.

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

The dynamic wild weather over the east is set to wind down later today as the low pressure system sitting over central NSW begins to weaken and the system opens up into a broad trough through the weekend and remains slow moving. The ridge to the south may allow a bit more stability and drier air to come into the picture over NSW so the coverage of rainfall not as widespread early next week as we saw in previous runs, but will watch. Another element that may save the east from further torrential rainfall will be a fast moving wave over the southeast mid to late next week which brings the chance of showers and thunderstorms, but knocks an westerly wave of deep moisture back to the east through the Coral Sea and ridging building in over the eastern inland for a couple of days. So those two elements may afford the east a few warmer and drier days. Will watch trends. Otherwise the west and central parts of the nation as mentioned yesterday, smooth sailing and routine weather over the northern parts of the nation where rainfall numbers are increasing in line with the deepening moisture levels.

12Z Euro - Precipitable Water Anomalies - Next 10 Days

The deeper moisture layer is starting to contract into NSW and QLD today with a cooler southeast to easterly flow through VIC and SA, that is entering the southern and western portions of NSW where heavy rainfall has caused flooding in the past 24hrs. The humid air is still likely to hang up over QLD and northern NSW through the weekend and into next week but perhaps the dynamics aloft is not as supportive for a return to heavy rainfall, not convinced of that idea but something to watch. Drier air over the western interior comes into SA but it does get overridden again by moisture seeping south from the tropics and the northwest Indian Ocean. The moisture profile is increasing throughout the nation as we go through the first week of December so rainfall numbers will increase for the nation as we come into the first week of December as the east continues to be wet and humid,.

12Z Euro - Rainfall Accumulation - Next 10 Days

Rainfall is continuing to contract into the east. More on this in the video.

12Z CMC - Rainfall Accumulation - Next 15 Days

Watching that trend of bringing moisture southeast and south from the NT into the eastern states through the first week of December. Also noting numbers are increasing over SA and WA as well, which is indicating that the broad easterly wind regime under the positive SAM looks likely to unfold into early December

12Z GFS- Rainfall Accumulation - Next 15 Days

Noting that the bias of rainfall continues to the east for the medium term as mentioned throughout this week, we need this current system to come off the board by tomorrow to get a better look at the medium term rainfall for the east. The west, humidity is likely to return again with rainfall chances coming up into the first week of December.

Looking further ahead into December generally rain wise

12Z GFS- Rainfall Accumulation - Next 5 Weeks

Additional rainfall for the east is problematic through December and flood risks remain very high as we track throughout the next 4 weeks. The tropics are set to see more active weather. Moisture will be drawn out of the Coral Sea and the northern tropics which will lead to significant storm chances returning to all states. So out west, enjoy the drier weather because the stormy weather will return.

12Z CFS- Rainfall Accumulation - Next 6 Weeks

The rainfall stated here is additional rainfall to come on top of what is forecast today. That is significant for December for the east and with the La Nina yet to peak, the impact of this rainfall verifying nationwide, would lead to more flooding and potentially bigger floods into 2022.

More details coming in the next 6 week outlook coming up mid morning.

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