The remainder of the state though remaining dry for the next week with high pressure slowly weakening.

But the most interesting weather over the coming week will likely be over the southern parts of the state where the temperatures are set to surge well above the average with strong winds. That airstream is fairly moist and so cloud will develop during Saturday afternoon before thicker clouds Sunday sees rainfall develop along the NSW border.

Moisture has already started to pool ahead of the frontal weather moving in from WA today, this is only going to increase ahead of the drier southwest surge during early next week.

That rainfall will likely spread through the southern districts on Monday ahead of a colder shift later in the day into Tuesday which will enhance the rainfall a little.

Tuesday into Wednesday, the air will dry out with a colder southerly moving in, that's as new high pressure ridge begins to nose in from the west and by Wednesday, the temperatures should have retreated back to seasonal values.

There may be a frost risk Wednesday or Thursday morning, yes even after the low to mid 30s this weekend! So growers be aware!

Then all eyes are on the moisture that begins to develop with an easterly wind and also on an upper trough that will be drifting through central Australia later next week into the weekend, can that combine with the moisture to produce rainfall? That remains to be seen and more on that can be found in the medium term forecast issued earlier today.

GFS in the medium term seems to be going all in with the moisture supply, can't quite connect the dots in terms of rainfall output but certainly some interesting signals continue in mid month.

The Euro in the short term shows the moisture developing over QLD next weekend and deepening thereafter in line with GFS but has a deeper moisture source coming into WA with a strong cold front at the end of next weekend. So there is plenty to watch while the pattern begins to flip over the nation. You can read more about that in the medium term forecasting.

Let's look at short term modelling

00Z GFS Surface Pressure Pattern for the coming 16 days

The pressure pattern is becoming unstable with a warm to hot moist northwest flow beginning to be lifted by the cold fronts and troughs moving out of the west. We will see rainfall breaking out over SA, VIC and NSW during Saturday and then into most of NSW and southern QLD during Sunday as the trough lifts northwards. The second front will lift the remaining moisture over the inland of NSW and drawn in deeper moisture through southern QLD and northeast NSW with the rainfall tending heavy at times about the GDR. The southern areas will see widespread showers developing during Monday and Tuesday with the passage of the front with hail and thunder over VIC and southeast SA. The weather then returns to dry through most of inland areas of NSW and SA from Tuesday though showers may continue in shallow moisture in onshore winds with light showers for coastal SA and VIC. The weather will take to this time next week to settle back to fine and clear weather for all parts of the southeast

00z GFS Rainfall for the coming 16 days

Rainfall is largely unchanged from overnight and this morning with the rainfall connected to the westerly wind regime, two frontal passages and the deepening moisture supply streaming in from the northwest ahead of the fronts as they rush through. There could be more rainfall with the feature coming in later this weekend into early next week with moisture stacking up in the upper northwest flow over southern inland areas but more pronounced into NSW. The weather is expected to ease from mid week as high pressure comes in so you can see no more additional rainfall under stable air from next weekend, that carries through to mid month over the southeast states, while rainfall returns to northern Australia and back over WA. The moisture in easterly winds will likely bring back showery weather to the east coast with that moisture then surging inland as per the medium term forecast guidance lifting rainfall chances mid month.

00z GFS Precipitable Water Anomalies next 16 days

As you can see from above, the moisture deepens over northern Australia, it is now a matter of whether the upper troughs can link into the moisture to produce widespread rainfall, which as I have said, modelling will show and then take away and then bring back. The model waltz will continue for a while.

00z Euro Surface Pressure Pattern for the coming 10 days

The pattern largely unchanged from this morning with two frontal waves tapping into large amounts of moisture streaming out of the northwest and extending over VIC and NSW, then into QLD this weekend into early next week. We have already seen that take place this afternoon with the moisture returning through the southeast inland with a weakening trough and moisture surging southeast. We see a front come through Saturday with the last of the fronts move through Monday through Tuesday with a colder southwest flow redeveloping. The weather will clear under that high pressure system moving in as the westerly winds retreat south but it may take up to a week from today for coastal areas of VIC, SA and TAS to clear totally. Inland areas should dry out quicker over the southeast. Note the upper trough over QLD later in the outlook and another long wave building off WA next weekend, these two areas will be the focus of medium term forecasting over the weekend and may provide the next batch of rainfall into the second week of August, that remains unchanged this evening.

00z Euro Rainfall for the coming 10 days

Rainfall increasing with the first system passing through the eastern inland with moisture becoming stuck ahead of a slow moving trough Sunday into Monday and then the drier air will move northwards with the secondary feature during Tuesday bringing a drier airmass. Then note the moisture returns in easterly winds for the east coast and showers about the NT coast and Top End signal the return of humid and hot weather over northern Australia, well ahead of schedule, which may play into mid month rainfall over inland QLD.

00z Euro Precipitable Water Values next 10 days

The Euro is similar to the GFS with moisture likely to reset under the new high pressure system next week. We can see a good supply of moisture coming in ahead of frontal weather over the southern and eastern states over the coming few days, leading to once again light to moderate follow up rainfall. The northern inland of NSW and southern QLD could surprise during Sunday and Monday as an upper trough deepens with the second system surging northeast bringing a colder southwest shift to the southeast state. In the later part of the next week into the weekend, we can see moisture developing over QLD and WA, where this will be the focus of the medium-term forecasting as two large cloud bands could develop in response to the moisture and troughs combining. Rainfall coverage next weekend is hard to pin down and better clarity will come Sunday night with the forecast packages and during early next week once the long wave over the southeast moves east.

Rainfall for the next 10 days

Rainfall unchanged from this morning, with the upper trough still lurking on some of the members tonight so I will leave rainfall for northern areas in place. The rainfall over the south is unchanged but I could lift rainfall totals for the southern inland during the morning if the guidance slows the rainfall down through QLD on Monday.

More weather details to come!! Have a great Friday night.

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