The central western NSW town of Parkes, with a population of about 10,000, has been isolated by floodwaters and areas of both the state's south and north are facing possible evacuations.
"The main focus is flash flooding rather than river flooding in Parkes," an SES spokesman told AAP.
"The expectationis that when the rain begins to ease, that water will fall," he said.
The owner of the Parkes Hotel, Samantha Dunlop, said the town was completely cut off but coping well.
"We're cut off. I've had to close my kitchen because my kitchen is flooded," she told AAP.
"The people who are further out are pretty well equipped. They have their big four-wheel drives, it's the silly kids on their P's that get stuck in this kind of water."
Ms Dunlop said the town was "resilient" and banding together to get through the crisis.
"The big thing I think is just what this has done to the harvest - it's just heartbreaking.
"A decade and a bit of drought has made people pretty resilient and there's no sense in railing against something like this. You just come together as a community and that's something we've been doing for a really long time anyway."
The automatic weather station at Parkes airport recorded 106mm of rain in the 24 hours to 9am (AEDT) on Friday.
Meanwhile, two properties near the southern NSW town of Jugiong have been evacuated as strong overflows from the Burrinjuck Dam on the Murrumbidgee River continue to threaten the area.
An SES spokesman said the increased flows had reached 175 thousand megalitres per day resulting in adjusted flood warnings and possible evacuations for downstream towns of Gundagai and Wagga Wagga.
"We've had some very heavy rain in the Canberra area that's working its way ... down into the back of the Burrinjuck dam and that is resulting in very high levels of water (spilling)," he told AAP.
In northern NSW, Coonamble is isolated by floods from the Castlereagh River and the small town of Pilliga is cut off by floodwaters from the Namoi River.
Some properties along the Macquarie River are also isolated.
SES helicopters are on standby to provide food and any other necessary assistance to all these areas.
