A rain event is expected to start on Friday and last until early Sunday, bringing between five and 20 millimetres in most parts of NSW in a line from just east of Broken Hill through to the Great Dividing Range.
A low pressure trough is being fed by moisture from both the Tasman Sea and the Coral Sea, a sign that finally a negative Southern Annular Mode (SAM) was letting rain-bearing lows further up into the continent after a recent blocking event.
The rain will be variable, according to the Bureau of Meteorology, in many districts, as some of the rain will arrive through storm activity.
It was also possible some areas will get a lot more than the predicted 5mm-20mm.
It comes at an important time in the cropping season as many northern crops were on their last legs after a good start. Many crops in the Goodooga area were suffering.
NSW is on track for its best harvest since 2016.
Bureau of Meteorology forecaster Stephen Stefenac said most of western NSW would get between 5mm and 20mm, from the Victorian border up to the Queensland border. The line of rain was expected to start just east of Broken Hill.
Broken Hill might only get 1mm - a distressing result for station owners suffering one of the worst droughts in history.
"It starts on Friday and it's a mixture of showers and storms, so there could be a lot of local variation in the event and could make it a bit tricky. It will taper off on Sunday and spread to the coast, but we predict that there will be between 5-20mm in most areas west of the divide."
Weatherzone's Ben Domensino said "widespread showers and some thunderstorms and snow will affect a broad area of southern and eastern Australia at the end of this week".
"A large pool of cold air approaching Australia from the south will interact with warmer, moisture-laden air from the north to produce several days of dynamic weather in parts of South Australia, Victoria, NSW, and Queensland from this Friday. Some of this weather could persist into the first half of next week as well.
"On Friday, widespread showers and some thunderstorms will affect Australia's eastern inland from central Queensland down through western NSW into northern Victoria."