NSW - WINDY AND MUCH WARMER TODAY THEN THE SHOWERY WEATHER RETURNS.

An active front that gave 120km/h winds and 30mm to Perth is now in the Bight, it is weakening, but the gradient winds ahead of that front are expected to reach gale force through the southern and southeastern states, dragging in milder air from the interior. The front itself has a decent band of moisture on it.


Satellite Imagery

You can see the pair of fronts over in WA, the lead system has peaked and is not in the process of weakening on approach to the east, it will still bring a band of light rainfall and those high winds over the next 24hrs.

That moisture is expected to be lifted into areas of light rainfall as it approaches the region, with moderate falls possible for the southern inland and the Southwest Slopes and ACT. The falls generally less than 3mm for the northern inland and near dry closer to QLD.


The ridge strengthens to the east during Thursday sending the state into a much warmer northwest flow, some locations reaching the low 30s in the far northwest with that air modifying as it tracks southeast, with the warmest weather since May easily achieved.


This is ahead of the next cold front with another round of gales and a more potent rain band, the front approaching during later this Friday will be stronger as it passes through the state. Moderate rainfall for the southern half can be expected, including the Lower Western.


Sunday looks milder with showers easing however now there are signals that a stronger system may make it through the gate for early next week before ridging takes hold, so we are starting to see some better agreement this morning.

Lets look at modelling


12Z GFS Surface Pressure Pattern for the coming 16 days

As you can see the two frontal boundaries this morning coming through the southwest, that is still expected to sweep the Bight and come into the southeast over the coming 24hrs. That is leading to the severe weather in parts of the region. Rainfall will be widespread with this feature but mainly light falls for NSW. The system whips through by Thursday. Another system approaches this weekend with rainfall moving through the state later Friday into Saturday, best of the rainfall falling over the south. Another system approaches early next week and that looks to have the most potential for rainfall statewide. In the medium term, we are starting to see that pattern flip moving into the shorter term forecast window. That may lead to a drier and settled spell.

12z GFS Rainfall for the coming 10 days

Rainfall largely unchanged from last night with the rainfall most widespread with this system coming through during the next 24hrs. There is another weak system coming through on Friday with more light rainfall for the southern inland, then a stronger system early next week. Any of these systems in the coming 7 days could produce widespread falls, as the models are having a hard time in predicting the wavy flow.

12z Euro Surface Pressure Pattern for the coming 10 days

Very similar to GFS, the wavy flow coming through during the next week looks to bring the most widespread falls the further south you go. The system coming during the next 24 hours brings the most widespread falls, before a weaker feature during Friday into Saturday, then another system early next week could bring more widespread falls. That is ahead of the pattern flip in around 7-10 days time with a high moving in to settle the westerly wind belt down.

12z Euro Rainfall for the coming 10 days

The rainfall is largely unchanged for the coming few days, but this run has dropped the widespread heavier rainfall with the system Friday but has still got reasonable rainfall again the further south and southwest you go. The system next week could produce more widespread rainfall before the high ridges in, with the system peaking over SA and VIC before it passes into the Tasman Sea in around a week's time.

Rainfall for the next 10 days

Rainfall is largely unchanged with the modelling flipping and flopping all over the place with the three systems during the next week, but one of those systems will bring more widespread moderate rainfall for the southeast. The system coming through during the next 24hrs could bring 10-20mm for some parts of southern NSW and up to the Central Tablelands. Then another 5-10mm during the weekend with the weaker feature (GFS had 10-30mm last night for that feature, has not got it today). The most widespread rainfall could be as the long wave passes through during early next week with a low possibly forming on the wave, that would see 10-30mm again through much of NSW during this period, then clearance.

Today is Climate Update Tuesday. I will have those details a little later this morning.

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