LATEST ON THE RAIN EVENT AND BEYOND IN 06Z GFS UPDATE

As promised, across the modelling for the sequence coming up. It is still looking rather tricky to pin down the rainfall event for the eastern inland, but there are growing interest around the heavy rainfall about the coastal areas between Rockhampton southeast to about Noosa at the moment, with the trough amplifying as it moves towards the coast and convergence developing in this region producing heavy rainfall.


I will pencil in a low flash flood threat on current trends in the modelling for Friday and Saturday but again the clarity on these elements remains low confidence.


But that said, the rainfall trends are positive for areas of QLD still suffering deficit.


GFS 06z run - Rainfall for the next 10 days - Valid Tuesday 29th of June 2021.

Note the heavy rainfall just along the immediate coastal fringe. This has moved around a bit in modelling as you can see below. Scattered moderate falls with isolated heavier falls through the southern and central inland of QLD could also be experienced through the northern and central inland of NSW too. Very tricky to forecast who gets what still.

Euro 00z run - Rainfall for the next 10 days - Valid Tuesday 29th of June 2021.

Noting the heavy rainfall along the coastal fringe, some of these totals if it comes down all at once during Friday and Saturday does pose a low end flash flood risk from the Wide Bay through to the Northern Rivers of NSW, with the zone become more defined in the coming days. Good rainfall for those who want it, and not such great news for those who do not want it. The rainfall through much of western NSW and into the southeast for a system next week in particular.

KMA 00z run - Rainfall for the next 10 days - Valid Tuesday 29th of June 2021.

Significant falls being analysed by this particular run of KMA in excess of 200mm along the immediate southeast QLD coast and into the Northern Rivers, prompting my heads up for potential flash flooding if convergence develops along the coast. Away from the coast, solid rainfall for much of central and southern inland QLD and northern inland parts of NSW.

ACCESS G 00z run - Rainfall for the next 10 days - Valid Tuesday 29th of June 2021.

Similar to Euro and KMA, heavy rainfall possible along parts of the Wide Bay and Southeast QLD coast with covergence possibly leading to flash flooding (low risk) during Friday into Saturday. This particular run has heavy rainfall with some spots exceeding 100mm of rainfall from the event through inland QLD and northern NSW (very low risk).

For those wanting an update beyond this rain event, here is the latest data from the GFS model for upper level flow pattern and the precipitable water values.


GFS 06z run - Upper flow pattern at 18000ft next 2 weeks - Valid Tuesday 29th of June 2021.

Strong upper trough will roll through the southeast and help to invigorate a trough later Thursday into Friday producing widespread rainfall over the east and a cold outbreak over the southeast. The confidence still remains low for the cold outbreak configuration but the rainfall chances associated with the trough are increasing in coverage and intensity so more updates in my AM edition of the National Weather Picture. Otherwise the systems clear early next week with the focus of weather shifting back to the west with a severe weather event with heavy rainfall and damaging winds.

Then from there it is still looking like the westerly wind belt will be quite the dominant feature into the latter stages of next week into the second week of July with elevated rainfall chances for southern and western parts of the nation.

GFS 06z run - Precipitable Water Values next 2 weeks - Valid Tuesday 29th of June 2021.

Moisture continuing to make advances towards the southeast with cold fronts trying to link up with those in feeds to create larger rainfall events. At this stage GFS is on again off again with the rainfall distribution but the moisture is absolutely 100% there for more rainfall to develop out of the Indian Ocean next week to bring more cloud and rainfall through interior WA to start with and over the southern and eastern interior mid to late next week.

GFS 06z run - Surface Pressure Pattern with rainfall distribution - Valid Tuesday 29th of June 2021.

Rain event looks pretty good for the east with the cold outbreak and trough easing through the weekend and clearing Sunday. Then the focus shifts back to WA and then over southern and western Australia. GFS tries twice to bring through weak cloud bands ahead of the third major event for the end of the period which is around the 12-15th of July. I firmly believe there will be rainfall before this point.

More weather details coming tomorrow with the National Weather Picture AM Edition. Then I will have updates and analysis through the morning of the weather events over the coming week. Spread the word to your friends, I am here now supplying even more information for those who need it most from morning to night.