Rural and regional NSW is "on edge" after heavy rain and flash flooding while Sydney was spared the worst of the wild weather that has hit the state.
Emergency services have performed 28 flood rescues in the last 24 hours as of Sunday afternoon, with 21 of them overnight.
Five emergency warnings have been issued across NSW, from Dubbo to the outskirts of Sydney, with residents told to prepare to leave.
The evacuation orders are among 94 warnings issued across NSW, including 45 advice-level warnings and 44 watch-and-act warnings.
State Emergency Service commissioner Carlene York urged people to be vigilant after a night of rescues, the majority being people who'd attempted to drive through floodwaters.
"It is very dangerous out there on our roads and we are seeing a lot of flash flooding and obviously the rivers are still rising," Ms York said on Sunday.
Emergency Services Minister Steph Cooke said Sydney had been "fortunate" but NSW is expecting another big system to hit on Wednesday.
"Communities in rural, regional and remote NSW; they'll be on edge for the next few days while we wait for another big system to arrive," Ms Cooke said.
"We are in for a long spring and summer in relation to wet weather conditions."
Ms Cooke said floodwaters would cause problems for inland communities for months.
The Bureau of Meteorology's Jane Golding said NSW could expect a series of weather fronts to pass through the state.
"We've seen totals far more than what we would normally see at this point in October," Ms Golding said.
Evacuation orders were active for the Oura Beach Camping Area outside Wagga Wagga, the Western Plains Tourist Park at Dubbo, the Riverside Ski Park in Cattai, and parts of Agnes Banks and Lower Portland.
Residents along the Hawkesbury River west of Sydney have been told to prepare to evacuate with dangerous flooding predicted.
Four evacuation centres have been set up, including three in and around Sydney and a fourth in Dubbo.
Major flooding is occurring and expected across the state, including in Gundagai from Sunday afternoon and several locations along the Lachlan River.
In the NSW's central west, the Bathurst 1000 was marred by a series of crashes with conditions hampered by the torrential rain the area had seen.
Meanwhile in Victoria, heavy rain drowned out a wine and music festival on Saturday, with major flood warnings for parts of the state even as rain eased.
Emergency services issued a watch and act message for communities in central and northeast parts, including the towns of Charlton, Avoca, Laanecoorie and Cowra near the Murray River.
