A significant band of rain is bringing heavy showers, thunderstorms and strong gusts across New South Wales, as widespread flooding continues and forecasters warn of possible landslides.
A trough tracking over NSW towards the coast is developing on Saturday and is likely to bring intense rainfall and the risk of flash flooding, the Bureau of Meteorology's Helen Kirkup said on Friday.
Six hourly rainfall totals of 30 to 50 millimetres are predicted in the Central Tablelands, the Hunter region and metropolitan Sydney, with isolated areas expected to receive up to 70mm.
After a soggy week in NSW, heavy falls on already saturated grounds will heighten the risk of landslides and debris falling across roads, Ms Kirkup said.
While the worst of the weather is forecast for Sydney, the Hunter region and the Central Tablelands, other areas can also expect rain.
The system is expected to blanket the state, with widespread showers forecast from the Mid North Coast to the southern end of the state.
Damaging winds are forecast through the Sydney metropolitan and Illawarra coast on Saturday through to Sunday morning, with winds of 60 to 70km/h and peak gusts of more than 90km/h.
Campers at the Bathurst 1000 have been warned of muddy, stormy and potentially dangerous conditions, with heavy falls predicted across Mount Panorama on Saturday and Sunday.
Up to 100mm of rain could fall on the tens of thousands of fans expected to attend, potentially leading to flooding along the Macquarie River in Bathurst.
Free sandbags are available in the town, while volunteers are checking in with residents and tourists camping near the river.
As rain continues to soak much of NSW, and flood peaks flow down already swollen rivers, the bureau has warned of a widespread risk of significant riverine flooding for multiple inland catchments.
Major flooding is occurring along the Macquarie, Darling, Culgoa and Lachlan rivers.
Renewed flooding is a risk at inland and coastal catchments including the Gwydir, Namoi, Macquarie and Belubula rivers, Mandagery Creek, the Lachlan and Bogan rivers, Colo River, Wollombi Brook and Lower Hunter rivers.
Melbourne downpour
Meanwhile, a downpour in Melbourne delivered half of October's average rainfall in one hour.
Some suburbs received 30 millimetres of rain in as little as 20 minutes on Friday.
There were fears a private dam in Craigieburn could collapse, with emergency services and engineers on site and a nearby major road shut down as a precaution.
Authorities are bracing for major flooding on Saturday along the Avoca River at Charleton, northwest of Bendigo.
A major warning was issued for the Loddon River at Laanecoorie, east of Bendigo.
The deluge on Friday followed a night of wild weather, with the SES receiving more than 600 calls for help in 24 hours.
The Evoca and Maryborough areas in regional Victoria received 50 to 65mm in an hour - roughly one month's worth of rain.
Areas around Frankston, Bayside, Woodend and the Maryborough district were also hard hit.
Two cars became submerged in one metre of water in South Melbourne while other vehicles became stranded at Seaford, in the city's south-east.
State Response Controller Tim Wiebusch said he was disappointed at least 15 people attempted to drive through flood waters.
"We know the single largest death or cause of death in flooding is people attempting to drive through flood waters," he said.
"Driving through flood waters could be the last decision you make."
More than half of the calls for assistance related to the impacts of flash flooding such as leaking roofs.
There were over 120 requests for building damage, with most related to fallen trees.
Heavy rainfall was expected to continue in northeast Victoria on Saturday, before conditions ease on Sunday.
