MORNING WEATHER UPDATE - THE RAIN HEAVY OVER THE EAST TODAY, SEVERE STORMS ABOUT MULTIPLE STATES.

An active Sunday of weather is on the way and we have warnings in place for heavy rainfall leading to flash and riverine flooding through NSW.


Storms have also been active overnight through NSW and QLD with locally heavy falls. They are ongoing this morning as well.


For much of southern NSW, Victoria, SA and eastern WA, it is settled under a ridge, while troughs on the periphery of the ridge are tapping into deeper moisture leading to the severe weather risks across the board.


The tropics also seeing an increase in activity which will support the next rainfall event through QLD and NSW.


FORECAST

Rainfall Next 10 Days

The rainfall is still expected to be very efficient over the east and northeast of the nation with persistent troughs and high humidity levels. The signals are not changing nationwide, it is now a matter of placement of that heavier rainfall over the NT, QLD and NSW. The west will see a decent storm outbreak today and tomorrow before dry and hot weather resumes. The central and southeast will see that system mid week before it hangs up over the eastern parts of the nation and combines with that deep easterly flow with widespread rain and thunderstorms to persist.

Thunderstorm Forecast Sunday

Thunderstorms are ongoing this morning through NSW and QLD with large areas of rain with heavy falls about. These thunderstorms will increase in coverage, however the cloud cover may mitigate the severity of thunderstorms. Heavy rainfall leading to flash flooding continues to be the major concern today over southern QLD and in packets of NSW.

Harvest - WHEN IS NOT GOING TO RAIN!


WA - Drier weather develops from mid week and a hot dry easterly will take us through until the start of December


SA - Only isolated showers expected through Ag Areas with the majority of rainfall expected further east. A few thunderstorms possible mid week then drier weather resumes with ridging for a good part of the back half of the week into next week.


VIC - Mixed odds, scattered showers and storms with high humidity mid to late week moving slowly into NSW during the coming weekend. Drier weather will develop earlier for western areas later this week and that will remain in place for a while under a ridge.


NSW and QLD - No chance of drying out for about a week at this stage. Some drier air may start to emerge through western and southern districts from as early as this coming Saturday. But no real dry phase expected for the east coast and into QLD.


DATA


18Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 16 days

A dynamic and complex weather pattern continues to unfold with severe weather risks in the east and west today with scattered to widespread thunderstorms forming in humid and unstable air. The weather over the north is tending more seasonal, humidity values increasing and rainfall becoming more regular. The weather from the west today, moves east through SA and into VIC mid week with isolated to scattered showers and storms and humid warm air, but this trough again deepens over the eastern states with showers and thunderstorms becoming more widespread. This is in addition to the severe weather and heavy rainfall about today which we have covered off for the past week. Drier air may return the south from later this week into the weekend, and hopefully sweeping the humidity out of NSW and parts of QLD which will be sitting under enhanced rainfall chances for this week.

But as you can see, there is more rain and thunderstorm activity into early December with the return of high humidity, once again over the north and east and another impulse down the west coast of the nation too.

18Z GFS - Precipitable Water Values - Next 16 days

Deep moisture has begun to engulf the north, central and eastern parts of the nation, however the moisture levels are set to increase further this week, leading to heavy cloud cover, heavy rainfall and severe weather potential. The drier air will be pushed back to the west of the nation with a significant period of warmer and drier weather under high pressure. The northern tropics will see seasonal values develop, but these higher moisture values will be drawn south via the upper level winds. Over in the Coral Sea, pay attention the westward moving waves which will crash into QLD and NSW which increases rainfall through December. There is another impulse of moisture out west along the jet stream from Indonesia, southeast into the western interior in the medium term.

18Z GFS - Rainfall Accumulation - Next 16 days

Latest GFS has backed off the heavy rainfall totals for the east coast, but that is just conditional, falls of 100-300mm for parts of the east coast is reasonable over the coming 10 days with additional rainfall beyond this. The tropics tending active (note PNG). The majority of the nation should be impacted by heavier atmospheric moisture levels which will support efficient rainfall producing thunderstorms and thick cloud cover, leading to below average temperatures in the east.

12Z Euro - Rainfall Accumulation - Next 10 days

The east is very wet still across all data sets, with some more aggressive than others. But the overall trend is, eastern VIC most of NSW, QLD and into the NT, wet this week before we see the moisture beginning to be shifted north and east through the nation next weekend, opening the door for a little break for those harvesting in the east.

12z CMC - Rainfall Accumulation - Next 10 days

Note the bias as per the Euro over the east of the nation and the tropics turning wetter still. The showers and thunderstorms are expected to be more widespread over inland areas of Central and Western Australia through the early parts of December, the heat values out west will enable more instability to build and the heat troughs to become deeper supporting more inland convection.

More weather coming up this afternoon - remain weather aware today.