NSW - WARM AHEAD OF A CHANGE MOVING THROUGH WITH RAIN FOR THE SOUTH.

The northern areas of the state likely to remain mostly dry for now with the main moisture surge being lifted by the front as it crosses over southern areas of the state.


A band of cloud is approaching from the west, so though it may be sunny over much of the state this morning, the weather will warm up quickly, become very windy and then rain developing from the west. There is moisture through northern NSW that is moving south into this front today, so cumulus clouds will thicken through this afternoon and showers breaking out ahead of the rain band.


Strong and gusty warm winds also likely to propel temperatures well above the average for coastal areas as well.


Severe wind gusts are possible about the Alpine areas and also with any organised line of showers or storms that form as the front passes east through the south. There have been winds of 135km/h over Alpine areas so far this morning.

The weather expected to dry out over the southern and western inland during Thursday afternoon with a cooler westerly eases. Then Friday more settled weather expected for inland areas after a cold start.


A boundary that is left over from the change rolling through the south later Wednesday into Thursday may become stuck over the QLD/NSW border and interact with some modest moisture via the southeast to easterly winds. That will see showers move inland later this weekend into early next week.


Watching this boundary in the outlook period - especially from Sunday onwards.

Coastal areas could see showers increase, mainly north of Newcastle this weekend with moderate falls.


Next week remains still very tricky to pin down, with the main weather starting to move into the 7 day forecast envelope, meaning the weather should become easier to forecast in the coming days, today the deterministic data is drier so what people are seeing in the basic modelling sites is a drier look, but as I keep saying, the broader data sets are wetter so that uncertainty will continue in the medium term. More on that later this morning.


Lets look at modelling


12Z GFS Surface Pressure Pattern for the coming 16 days

The front passes through the southeast today bringing a gusty and warmer northwest flow through the eastern states, with temperatures up to the high 20s and low 30s through QLD, a sign of the times. The moisture is limited to the frontal passage but has a decent rain band on the feature this morning through SA. That front is bringing rainfall into southwest areas of VIC and that will move through the remainder of VIC and into NSW this afternoon and evening. The weather clearing fairly quickly overnight. A cold airmass in the Bight should continue to weaken as it approaches the east but may still bring a few showers and storms to southern SA and VIC tonight. The weather essentially dries from Thursday afternoon with the showers decreasing and the weekend looks dry. The models next week really struggling what to do with the trough out of WA. Some bring it through and link it up with moisture and others say no deal and wash it out in a large high. So the low confidence continues for most of the east and southeast next week.

12z GFS Rainfall for the coming 16 days

Rainfall for the next week is confined to this system moving through the southeast today and clearing out tomorrow. Then high pressure ridges through and keeps the southern inland dry. The east coast will have an easterly wind return and that will feed showers along the coast with drier weather for the inland if this is correct. The medium term continues to be a dog's breakfast so watch this space as the modelling will continue to chop and change until Saturday or Sunday.

12z GFS Precipitable Water Anomalies next 16 days

Models continue to support the transportation of moisture from northwest to southeast across the nation, the Indian Ocean Dipole continues to support this to repeat itself over the next fortnight. We can see another deeper plume coming in from the northwest next week. More moisture being pumped in via easterly winds over NSW and QLD and the trade winds also brings moisture values above normal through north QLD and the NT. Today the data set here is suggesting the moisture will struggle to link up with the moisture but as I have said the broader data sets are wetter for inland parts of the nation with the bias of wetter weather through northern and eastern Australia mid to late month.

12z Euro Surface Pressure Pattern for the coming 10 days

The weather pattern is in good agreement with the GFS for the coming 4 days with the front passing from west to east today and clearing out during Thursday. A high pressure system will ridge in from the west and clear out the inland, while the west turns dry and warmer over the weekend. There may be a weak front that passes through the southwest of the nation during Saturday. Meanwhile an onshore flow will bring showers to the east coast, there is a boundary still expected to set up over the QLD and NSW border which may pull moisture inland, but can it be lifted into more widespread showers? That may be something to watch this weekend and next week. Otherwise the Euro is low confidence next week, like GFS is struggling to piece it all together over the nation with there no consistency in the guidance. So keep patient over the coming days

12z Euro Rainfall for the coming 10 days

Rainfall largely confined to the next 2 days with the cold front passing from west to east today with light to moderate falls. The weather then turns drier for the weekend into next week for most areas, though with the humidity returning with the easterly winds on the east coast, showers will be confined there north of Sydney. The weather turns unsettled from this time next week but how that looks remains to be seen. This morning the model has decided to drop any rainfall for the nation and only a cold front passing through WA is expected to bring the next wave of rainfall, drawing in some moisture from the northwest.

12z Euro Precipitable Water Values next 10 days

The moisture distribution is locked in for the coming 3-4 days across the nation with the cold front passing through with a moisture surge coming through the Indian Ocean, we can see that in real time now with areas of rainfall. Into the weekend the weather turns drier over the southern states but over the east and north moisture increases. The moisture profile increasing further next week with another surge of moisture rotating through WA and being picked up by a cold front, so minimally there could be a repeat system passing through next week similar to what we are seeing this morning over SA. However sometimes you see the models repeating a cycle that is active in real time in the short term, so expect the modelling to change. The moisture is still expected to deepen over the nation.

Rainfall for the next 10 days

No real change in my forecast chart this morning as guidance remains poor, the wettest period expected to be from tonight through tomorrow morning. The rainfall should be gone by lunch tomorrow. Then showers developing for the east coast in easterly winds, mainly north of Newcastle. Next week, no one can tell you how that will evolve, there will be a system lurking of some variety from next Tuesday or Wednesday. It is frustrating that is the current confidence levels. But it is a spring set up at the moment. Models struggle the most between August and November.


I will have a look at the medium term today and an Indian Ocean review to see how the Dipole is going and whether we will see more influence coming through the second half of August.
















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