And with a deep moisture profile in the region left over from the horrendous humidity and storm outbreak over the southeast and east of the nation as well as moisture being sheared off the tropical low over northwest WA and that too coming down the pipe into northern eastern NSW and southern QLD, the ingredients are there for a fairly robust rainfall event.
Unlike the southeast and interior, it is not based on if you get a storm, you know the deal on the east coast, significant rainfall via easterly winds into troughs along the coast spell heavy rainfall and flooding, and you only need one system to sit in the right spot for 2 days and some places can score 400-500mm in a sitting.
So things can turn quite quickly. While there is a risk of that occurring, that is considered quite low at the moment but the risk is not 0.
CMC Solution - Rainfall Next 10 Days
The CMC has been most aggressive on the rainfall outputs for the past few days and it is not without merit. The overall forecast remains low but this solution offers a glimpse of what happens when the trough sharpens on the coast and is cradled by a high to the southeast, pumping in deep moisture into an unstable airmass from the east. Inland rainfall also higher in this solution thanks to the tropical low adopting a slow track and moisture shearing off to the east in the jet stream bringing a broad rain band. Flash flood risk is moderate.
Euro Solution - Rainfall Next 10 Days
Showing the trough not as amplified through this period but still showery to develop this week, the heavier rainfall that the CMC has is not quite there. But the band of rain attached to the tropical low over the interior is greater and brings soaking falls throughout large parts of northern NSW and southern QLD with the southeast to get some rainfall. Southern areas of NSW and into SA and VIC mostly dry.
GFS Solution - Rainfall Next 10 Days
The GFS is the driest solution for the inland with the tropical moisture stay out west and have the least influence across the eastern inland. Still unsettled. The east coast will see showers, not as light as the Euro, but more in line with the CMC but cannot penetrate as far inland.
As you can see, each model has it's own take which makes forecasting this rainfall very low confidence.
Stay tuned to the forecasts this week as things could change drastically in coming updates, either drier or very much wetter.