Reasonable rainfall overnight for the Wide Bay and Burnett extending into the SE Coastal District, with the top fall of 77mm at Gladstone Radar overnight. 30mm in and around Hervey Bay with a light rain band sitting stationary overnight. This rainfall is some of the better winter rainfall in years for this reason.

Rainfall observed for the previous 24hrs over the Wide Bay and Burnett. Great falls for many in the region, with lighter falls back west towards the divide, however some areas inland did record 10-20mm Friday.

The rain band is now lifting out of QLD while NSW has been essentially dry and clearer since last evening, the east now starting to see the impacts of the high pressure ridge moving in from the west.

Looking at today, we can see the rain band leaving the QLD coast with a trough lifting offshore. The cloud will take a little longer to clear offshore, but improving conditions for the remainder of Sunday into Monday.

High pressure will move southeast of the region with onshore winds returning to the QLD and NSW coasts. This will propel showers to the wide sections of the east coast, with the heavier falls expected for coastal communities and lighter showers making it to the divide. The shower coverage will be more isolated south of Sydney being closer to the centre of high pressure.

High pressure making the journey to the southeast during early next week with that high becoming slow moving. The high will send easterly winds onto the coastline with low level moisture increasing bringing in showers and drizzle to the coast. The rule of thumb is the closer you are to the high pressure system over the southeast of NSW, the lighter the rainfall will be along the coast. GFS Surface pressure pattern for the early part of the week,

So a closer look at rainfall from QLD through to VIC over the coming 10 days. Showers as I have mentioned more likely about the coastal fringe and will see light to moderate falls accumulate over the course of 5 days of showers. So not one day will be a washout, just showers from time to time, very typical for winter.

Rainfall for the next 10 days - Valid Sunday 27th of June 2021.

Rainfall for the next 10 days - Valid Sunday 27th of June 2021.

This area is one to watch with the development of a trough along the east coast or inland of the coast, potentially bringing more rainfall just outside of the 10 days forecast envelope.

Rainfall for the next 10 days - Valid Sunday 27th of June 2021.

Showers will be about most of the NSW coast, though light falls for the southeast thanks to being under the centre of high pressure, where sinking air motion will be at its greatest.

Taking a look at that upper level disturbance and potential rainfall event just outside of the forecast envelope now with GFS.

The moisture/precipitable water shows the potential of rainfall chances increases in the day 8-14 window across the region. This is due to the SAM (Southern Annular Mode) becoming positive next week. This helps to bring easterly winds over eastern Australia, that is now being picked up in short to medium forecasting. It also is a precurser to inland rainfall in winter time over inland QLD and NSW. So positive signs perhaps for QLD.

Southern Annular Model - SAM forecast for the coming 2 weeks from the ensemble. Positive spike and then a return to neutral values/negative trend there after. This climatic driver is erratic and difficult to forecast ahead of time.

GFS SAM Forecast - is pinging the positive phase and that is why rainfall numbers are above average over the eastern inland and drying out over the southern coastline, but this can change rapidly.

The precipitable water that is then allowed to pool over the eastern inland increases, and with low pressure and colder air floating around in this period over the region, widespread rainfall is a LOW chance due to how far into the distance this event is!

So this is something to watch over the coming week here on the page.

GFS is probably the most aggressive on this approach so will use this as a guide to when it all comes together, but note that it is still a low confidence forecast.

GFS 18z run - Precipitable Water Values for the coming 2 weeks - Valid Sunday June 27th 2021.

Note the humid air being trapped over QLD and then extending back southwest into QLD. Some runs have brought this humid back into NSW as well, this particular run not so much, but just note that this will continue to evolve over this week. But with the PW values of 25-40mm, that would help to form a solid area of rainfall and thunderstorm activity if an upper disturbance approaches from the west or forms in the easterly flow along the coast.

GFS Rainfall for the next 10 days - Valid 18z Sunday 27th of June 2021.

Showers developing along the coast this week, and then by the weekend this model has been indicating a trough forming over the inland of QLD, NSW and into northeast VIC. I am keeping the confidence of that element at low confidence for now.

Lets compare with the Euro Model to show the uncertainty in the medium term range in the handling of the upper system later next week into next weekend.

The best model to use is the Euro Ensemble model which is made up of 50 members/data sets and this is the average of all these members. The average is important because it gives you a better idea about the confidence in the medium term. Certainly there is an increased risk of rainfall developing through the outlook period over inland areas of QLD and NSW, but up to 200mm? I think that is very low risk at this time and I am siding with Euro at this time.

Euro Ensemble Rainfall for the next 15 days - 12z run - Valid Sunday 27th of June 2021.

The deterministic Euro (single run/data set) pinging rainfall for inland QLD in line with the trough GFS has for the eastern inland with scattered falls. That does look like it will be an element to watch as we go through the week. But can it combine with cold air from the west and deeper moisture from easterly winds rotating around the high, as GFS suggests? Too early to tell.

Euro 12z run - Rainfall for the next 10 days - Valid Sunday 27th of June 2021.

Euro 12z run - Rainfall for the next 10 days - Valid Sunday 27th of June 2021.

So if you look at GFS which goes out to 16 days, this has caused quite a stir on social media, but the models giveth and the models taketh away. So just remember that even though this model is showing 100-200mm for inland QLD and about the southeast, it will change run to run. I will have more on that in this evening's national weather wrap at 6pm. I am not forecasting this rain event at this time.

Just because the models say this, many of you know who have joined this page and followed me for a while, that this is just not how it works, so watch trends.

For areas of inland NSW and into VIC and SA, which the charts above cover, it is looking more likely that a dry week will unfold until about Friday. That trough which is forecast to kick off showers and thunderstorms later in the outlook is being picked up by models, but the specifics will become clearer through the week and this information, now I can provide you, will be updated daily at greater detail.

Thank you for joining my page. You have the baseline subscription which may be enough for your needs to keep on top of what is happening weather wise, but I can go into greater detail with tailored forecasting for your property, with tailored charts and data. So email me at karllijnders@weathermatters.org for more details.

30 views0 comments