NSW - THE WEATHER EXPECTED TO TURN LATER THIS WEEK, BEFORE THEN SETTLED WEATHER.

It is a cold start for the inland this morning, especially in areas protected from the westerly wind regime. The skies clear along and east of the divide to produce frost patches for some as well. Very cold pocket through the southeast this morning where in the protection of the Snowies, -7C in Cooma.


Cold start over the southeast inland with temperatures still supportive of frost, but west of the divide it is somewhat milder with only a light frost about.

The weather is largely unchanged once again for the coming few days, with high pressure taking full control from today as the westerly wind belt moves into the Tasman Sea, so conditions not as breezy as yesterday and milder weather in bright sunshine.


Later on this week it is all about the pair of cold fronts passing through, now we are seeing more rainfall developing this weekend into Monday, the models shifting the focus of the potential more widespread rainfall to the early part of next week.


But it is the weather later this weekend that has more interest for NSW, but again there are differences in the modelling, and this will begin to become clearer as I have stated through the coming few days.


Euro Monday Afternoon - system further south.

GFS Monday Afternoon - System further north.

While that is does continue to express uncertainty, it is better that the more widespread rainfall is now moving inside the 7 day forecast window rather than further into the distance. That fills me with a little more confidence.


Lets take a look.


12Z GFS Surface Pressure Pattern for the coming 16 days

The pattern is largely unchanged for the coming days. Dry and quiet for most of the nation until later this week when the frontal weather over WA that will drive the moderate rainfall there finally moves across the southern parts of SA and into the southeast states, a deeper moisture profile could spread the rainfall out through Friday into Saturday. Another weaker front keeps the showers going over the southern states Saturday and Sunday. The weather north of the fronts passing over the southern states will be warm to hot and dry under the high pressure, so northern NSW, QLD, northern SA and into outback WA and the NT, the dry and hot weather will continue. Next week, the weather turns complex with modelling unable to come into agreement with the long wave passing through over the southeast. The system will ultimately drive a drier cooler change through the nation's south, but how much rainfall it will deliver to the southern and southeast states remains to be seen. There are more rainfall opportunities beyond this system to finish the month.

12z GFS Rainfall for the coming 16 days

I won't add much, but rainfall largely unchanged from last night, this will continue to bounce around in response to the system passing through later in the weekend into the early parts of next week, once that settles down in the guidance, then a more definitive rainfall forecast can be drawn for the southern and eastern states. Up north, humidity may bring scattered showers and thunder later in the outlook.

12z GFS Precipitable Water Anomalies next 16 days

From run to run, the models have high levels of moisture then the following run, introduces widespread dry air throughout the eastern and northern parts of the nation. This is why you see inland rainfall on one run, and nothing on the following run. So again lets see what the next few runs bring. It will continue to chop and change. The medium term also offers more moisture passing through the nation to finish the month but again the capability of pinning down a forecast at the moment beyond 7 days is tricky.

12z Euro Surface Pressure Pattern for the coming 10 days

The forecast pattern is largely unchanged for the coming week, though we are starting to see rumbling of inland moisture on the Euro for Central Australia, this has been appearing across other modelling as well, so will have to take a look at that in the coming days because that could offer rainfall opportunities for northern NSW and QLD. But for now the bulk of the rainfall is expected over the southern parts of the nation with the frontal passages.

12z Euro Rainfall for the coming 10 days

Rainfall largely unchanged for the nation, but keep an eye on that inland rainfall chances in the coming few days as that could provide a chance of rainfall spreading from Central Australia into northern NSW and southern QLD during the next two weeks. That is the nature of modelling right now that it is tricky to forecast when the ingredients for large scale rainfall to develop over inland areas will occur, but there have been multiple signals and I will call it signals for now. More on that later this morning.

12z Euro Precipitable Water Values next 10 days

Again the chopping and changing from run to run is why you are seeing the rainfall distribution chop and change. But again there are rainfall opportunities across the board as we finish the month and I do expect there to be more widespread rainfall developing as we go through September. The south will have a wetter end to August and that will creep over the southern inland areas of the nation.

Rainfall for the next 10 days

The guidance for the coming 5 days is unchanged with frontal weather clipping the southern parts of the state. That will see patchy rainfall for southern areas of NSW with cloudy skies further north and dry along the east coast. Later in the weekend it is flip and coin, the rainfall could move further north if the system cuts off into a low pressure system over VIC. But right now I am not factoring that in.


The ENSO update coming up later this morning looking at the chance of La Nina forming in the Pacific Ocean, this will have ramifications for the spring and summer season ahead.





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