A woman is missing in floodwaters in central-western NSW after a vehicle was swept off a causeway as rainfall records continue to fall.
Three people managed to escape the vehicle and make their way to safety when it was inundated at Cooyal Creek at Gulgong, north of Mudgee, on Sunday night.
Police say a 45-year-old male driver and two male passengers - aged 43 and 26 - survived but a third passenger, a woman in her 20s, is missing after getting free from the vehicle.
The search comes as two weather systems cause more pain for NSW residents in already flooded areas and emergency services prepare more people for evacuations.
More than 140 flood warnings and 15 evacuation warnings are in place across NSW, with almost every corner of the state at risk.
There are 550 State Emergency Services volunteers in the field, with reinforcements from WA due to arrive on Monday.
The crisis engulfing the state comes as more rainfall records are smashed after Sydney on Monday marked its wettest October - 286.8mm of rain - in the 165 years of record-keeping.
October is the third month to set a rainfall record in Sydney this year and Weatherzone reports Sydney's annual rainfall has reached 2387.6mm, easily its wettest year.
Residents at Lismore in the Northern Rivers region were told to prepare to evacuate on Sunday night amid the prospect of a third major flood in eight months.
Some low-lying parts of south Lismore are already under water, although the flooding is unlikely to be as severe as the inundation that hit the area earlier this year.
The Bureau of Meteorology said heavy rainfall eased over the northeast on Monday morning but widespread severe thunderstorms across much of inland NSW was predicted for Tuesday, bringing heavy rain, damaging winds and hail before conditions ease on Wednesday.
Moderate flooding is now likely along the Wilsons River at Lismore from late Monday morning, with major flooding possible from Monday night.
Emergency Services Minister Stephanie Cooke said authorities were keeping a "very, very close eye" on Lismore and the wider region.
"We all know how much those communities have been through this year," she told ABC TV.
There are also concerns about Moree in the far north, where the town is experiencing its worst flooding in a decade.
Farmers in the agricultural hub were just weeks away from harvesting crops, which are now destroyed.
"It's heartbreaking. There's no doubt the damage and devastation through that region will be deep and widespread," Ms Cooke said.
The Mehi River at Moree peaked at 10.5 metres on Sunday and is expected to remain above the major flood level (8.8m) into Tuesday.
Mayor Mark Johnson said there was a sense of relief on Sunday night when the river started to recede but also apprehension about the clean-up.
Other towns at risk of flooding include Hay, Wentworth, Ballina, Yamba and Maclean.
Evacuation orders are in place for Moree, Terry Hie Hie, Gunnedah and Carroll in the state's north, the Riverina town of Narrandera and Mudgee in the central west.
Meanwhile, a second system is bringing more rain to already saturated parts of the state.
Residents have been ordered to higher ground at Cummeragunja and Mathoura East on the Murray River, where floodwaters are expected to peak on Monday.
Authorities continue to keep a close eye on the southern border town of Moama, with major flooding expected on Monday when the Murray River peaks at 94.9m, which is higher than the 1993 flood.
Two hundred Australian Defence Force personnel have been deployed across the state.
Natural disaster declarations have been made in more than 40 local government areas, opening councils, residents and businesses for financial aid.
© AAP 2022