There is the potential for a slow moving soaking rain system later next week, over much of southeastern Australia.
It is early days yet (nearly a week away) so that puts it in the ‘low confidence’ category for now - but all four weather models are already on board, so that gives us some hope.
As always, the guidance will jump around as we head towards late next week, sometimes weakening, other times strengthening - so I advise you to wait until it is a few days out, and there is consistency amongst all the models in terms of timing and how much rain, before you put high confidence in this situation. It has a bumpy ride to get through before it finally arrives.
In the lead up we’re likely to have high pressure move on an angle to let humid air flow in from the Pacific, not just for Queensland and eastern NSW but spreading through western NSW, Victoria and parts of Tasmania and SA. This is the kicker we need to produce some decent rain.
The other necessary ingredient is low pressure, providing instability. The main rain event is likely to be driven by a cut-off low pressure system. In order to get rain that affects a large area we usually need one of these to be the driver. They are ‘cut-off’ from the westerlies to our south and can meander slowly, ensuring everyone in the area sees a drink.
This situation - moisture from the Pacific, running into a slow moving low - is often the best way to see proper rain if you are over inland parts of the southeast.
Potential rainfall over the next week (up to Saturday, October 19).
The latest projections show a large area from southeast Queensland, to eastern and central NSW, to much of Victoria, Tasmania and southeast SA in the yellow zone. This is 25 to 50 mm over the next week. The orange shading indicates more than 50mm.
Much of this rain arrives late in the week for the southeast (and still has low confidence), while Queensland and eastern NSW see it over several days.
Ahead of this low, we have warmer conditions, with air that slowly turns humid. Troughs are a feature in the weather pattern, but before the moisture can properly flow through, these troughs may have more bark than bite - with only local heavy falls from hit and miss thunderstorms.
Check the full details at Jane’s Weather to keep up to date on what the models are projecting for your spot. When you have all four models (with an 80% PoP), and looking at the PRO toggle shows you that the rain is all coming at the same time - that is when you get excited.
If you’d like an in depth analysis don’t miss my weekly video update - perfect if you have 20 minutes to spare!