The Bureau of Meteorology (BoM) has issued more than a dozen flood warnings across the two states in anticipation of the wet weather.
The BoM said “widespread rain and the chance of storms” will impact inland NSW from Thursday to Saturday.
“Increasing showers” are forecast for Sydney from Friday, with up to five mm of rain predicted to fall.
Moderate to major flood warnings are in place around Dubbo and Bourke.
“Moderate falls are possible about the western slopes, which may lead to renewed river rises,” the BoM wrote.
Meanwhile, Western Australia’s south-west corner has been dusted with snow.
Parts of the state have been shivering through it’s coldest weather of the year, due to a polar blast of air.
“Perth had its coldest day of 2022 to date yesterday with temps in the single-digit range for all but a few hours and a maximum of just 12.1C,” Weatherzone said.
The air driving the cold front is said to be “unusually cold”.
‘River City’ wakes to white-out as fog swallows city