Rain to soak every state as multiple low-pressure systems collide

Rain is on the way for every state and territory over the coming days, with some parts of south-eastern Australia expected to receive a drenching.

The mix of multiple low-pressure systems and upper-level cooler air is providing ideal conditions for wet, stormy and windy weather, reports weather data firm Weatherzone.

The unstable conditions took hold in South Australia, Queensland, NSW, Victoria, Tasmania, the ACT and the southern Northern Territory early this week.

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The rain is forecast to intensify across eastern Australia by Friday, before further showers spread over south-eastern states over the weekend.

Weather modelling suggests eastern and northern NSW and eastern Tasmania having a strong chance of heavy rain and potential flooding. Parts of the ACT, eastern Victoria and southern Queensland also have the possibility of major falls.

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In addition to the wet conditions, there is a warning of stronger winds and hazardous waves off the coast of NSW, Victoria and Tasmania.

The Bureau of Meteorology today issued a hazardous surf warning for the Byron, Coffs, Macquarie and Hunter coasts in northern NSW.

Western Australia won't be spared the wet and stormy weather either.

The damp conditions will make their impact from tomorrow when rain, thunderstorms and blustery winds are expected in the state's south-west.

Later in the week, a complex low-pressure system is forecast, with a strong chance of heavy rain, damaging winds and severe thunderstorms.