Communities in NSW's Northern Rivers region are again on flood watch with heavy rain lashing the area.
Forecasters were predicting significant rainfall overnight on Saturday and continuing to Monday, with flash flooding and riverine flooding likely.
The NSW SES says residents, especially those who have been flooded in the past, should prepare.
"While the current predictions are not as severe as earlier this year, low lying areas are still likely to be impacted," incident controller Tom Jory said in a statement on Saturday.
NSW Police said a man in his 30s had died in a suspected drowning on Saturday morning at West Ballina in the state's far north coast.
The Bureau of Meteorology warned of heavy rainfall over northeast NSW from Sunday morning, affecting those in Lismore, Grafton, Casino, Kyogle, Yamba and Maclean.
Falls of up to 150mm in six hours were possible in some areas.
More than 100 flood warnings were current around the state on Saturday night.
In the south, emergency warnings were in place for parts of Narrandera while residents in areas of Gunnedah in the state's north were ordered to evacuate.
Warnings were also in place for Moree and Carroll Village.
NSW Emergency Services Minister Steph Cooke said large parts of the state, including the inland and west, were in for a "difficult few days".
Emergency services are preparing for a busy weekend as the wild weather arrives, with volunteers handing out 30,000 sandbags a day.
"We are quite literally sandbagging the state," Ms Cooke said on Saturday.
Two hundred defence personnel are being deployed in Dubbo, Moree and the Northern Rivers, with two more Australian Defence Force helicopters coming online ready for night rescues.
Specialist swift-water rescue crews have also been dispatched to the flood-threatened north while others are in place at Dubbo.
The 12 local government areas added to the state's natural disaster declaration list are Albury, Berrigan, Carrathool, Cobar, Federation, Griffith, Hay, Leeton, Murray River, Murrumbidgee, Narrandera and Wagga Wagga.
© AAP 2022