Thousands of residents of Sydney and the NSW mid-north coast were given middle-of-the-night evacuation orders as rivers in the state threatened to burst their banks.

People in the Hawkesbury and surrounding areas were told to evacuate by 9am on Monday, including the Windsor CBD, McGraths Hill, South East Windsor, Wilberforce, Marsden Park, Riverstone and Schofields.

The Castle Hill RSL at 77 Castle Street was set up as an evacuation centre.

On the mid-north coast, residents of Kempsey were awoken just before midnight and told to evacuate immediately.

Evacuations were already underway in parts of Western Sydney over the weekend, as streets became submerged in rainwater and low-lying homes drenched.

The Bureau of Meteorology warned the danger isn't confined to the coast - the state's west could see increased rain from Monday as well.

More to come.

Originally published as River burst threat sparks snap evacuations

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