An unusual weather pattern for late autumn will bring rain to large parts of central and eastern Australia later this week and into next week, potentially delivering the highest totals in many months to some parched areas.

This is not a typical late autumn set-up. At this time of year, high pressure systems usually drift north, allowing cold fronts embedded in the band of mid-latitude westerlies in the Southern Ocean to push cool air and moisture over the southern portion of the country.

But the large, slow moving high pressure system currently centred over waters near Tasmania is blocking systems from the south. As air circulates anti-clockwise around the high, an easterly flow is dampening the east coast, with drier conditions inland.

In the 24 hours to 9am Wednesday, some handy falls of 25mm or more were recorded along the east coast, all the way from the Hunter region, just north of Sydney, to parts of Far North Queensland near Cairns.

As the persistent easterly flow interacts with a trough over Australia’s interior, widespread inland rain is expected to develop.

Let’s break down the rainfall potential in coming days in each state:

South Australia

Image: Predicted rainfall accumulation across South Australia by 9:30am (ACST) this coming Saturday, May 16, 2026, according to the ECMWF model. Source: Weatherzone.

As the map above shows, rainfall could develop across much of South Australia, especially the eastern portion of the state, by Saturday.

Adelaide rarely sees rain arrive from the northeast, an occurrence which is most common during a La Niña. (Currently, Australia is in a neutral phase of the El Niño–Southern Oscillation, or ENSO, meaning there is no La Niña or El Niño. An El Niño is expected to develop in Australia before the end of winter.)

But from Friday onwards, Adelaide’s wettest spell of the year could set in with rain arriving from the northeast.

Victoria

Our southernmost mainland state could see useful rain in most areas, with the lightest falls in Gippsland in the east. Melbourne is most likely to see showers from Sunday through to Tuesday.

As you’d expect with a weather event where winds have a northerly aspect, days in Melbourne will remain relatively mild. To date this month, Melbourne’s average maximum has been more than two degrees above the May average maximum of 16.8°C.

New South Wales/ACT

Image: Rainfall deciles for NSW from January to April, 2026. Source: BoM.

By the end of the weekend into early next week, this system has the potential to bring the first significant rainfall in months to parts of the state’s north and northeast which are shaded red in the map above. Western, central and most eastern parts of the state can also expect handy rain.

For Sydney, expect a continuation of this week’s showery weather – with any rain arriving from almost the opposite direction to this week’s southeasterlies.

Canberra can also expect a useful drop next week, after an almost totally dry first two weeks of May.

Tasmania

Image: Predicted rainfall accumulation across Tasmania by 10pm (AEST) next Tuesday, May 19, 2026, according to the ECMWF model. Source: Weatherzone.

The northwest and the state's west coast can expect heavier rain than the rest of Tasmania, with rainfall accumulation tapering off in the southeast corner.

While Hobart can expect some showers early next week, it won’t do a lot to alleviate the recent dry spell, in which four of the last five full months have seen below-average rainfall totals.

Queensland

Image: Predicted rainfall accumulation across Queensland by 10pm (AEST) next Tuesday, May 19, 2026, according to the ECMWF model. Source: Weatherzone.

This system should deliver rainfall to parts of western and eastern Queensland, with central parts of the state appearing likely to miss out on significant falls at this stage.

Birdsville, in the state’s normally parched southwest corner, has had an interesting rainfall year, with a record 177mm in February and further handy rain in March. The town’s average May rainfall is just 8.4mm, but that total could be exceeded on Sunday alone.

Brisbane's showery spell is also likely to continue into the new week.

Northern Territory

Locations in the southern NT like Alice Springs and possibly even Yulara (the town near Uluru) appear likely to see meaningful rain for at least two days from Saturday onwards.

There could also be some regular shower activity in the Top End even though the wet season is now officially over.

Western Australia

The only reason we’ve put Australia’s largest state last is that this system will have more impact on the eastern two thirds of the continent than the west.

Having said that, some eastern parts of the state could catch a piece of this system, with rain possible in some very dry outback areas.

The far southwest of the state, including Perth, will see showers from cold fronts this Thursday and Friday. The fronts will be steered away from more easterly parts of Australia’s southern coastline by the blocking high.