NSW residents told it's too late to leave as fire 'destroys' properties

Dan Bennett, currently living in Tathra, said his family had been celebrating his parents' birthdays at their home when crews in fire engines "screamed" into their street and told them to evacuate.

"All of a sudden [the conditions] just turned, we could see flames a couple of streets away. It just turned on a dime," Mr Bennett said.

"The smoke was so thick. There were lots of embers flying about."

His family, who are bunking down for a stressful night a relative's house in nearby town Bega, have since heard the fire swept through their street and most of the town.

"When we were getting in the car to leave, our neighbours across the road could see [the fire] behind our house," he said.

"We’re all safe, but our biggest concern is the house... "It's [my parents'] forever home - they have been there for about 13 years.

"It's going to be a miracle if it's still there."

Mr Bennett had heard the local supermarket, public school, bakery, chemist, bowling club, and holiday apartments had been affected in the fires, but the extent of damage to the town remains unknown.

Local resident Tas Fitzer left his family home and managed to evacuate to Bega with his mum, cat and dog in the car, while thick smoke was “billowing” across the town.

With no idea whether his home has been damaged, for Mr Fitzer the most difficult thing is waiting to hear about the extent of devastation to the town.

"Our closest friends we know are all safe, but there’s the acquaintances… that we haven’t been able to get in contact with," Mr Fitzer said.

“And the disappearance of the town as a whole - we will have friends who have lost their homes, and businesses lost, it’s just going to be devastating.

“The waiting, and not knowing, is the most stressful thing.”

Shane Fitzsimmons, NSW RFS Commisioner, told Channel 7 News that the "large, fast-running fire" had burnt "right into the back and all in and around the community of Tathra".

Mr Fitzsimmons said the number of houses damaged or destroyed could be "in the dozens", and conditions remain "very dangerous and volatile" in the area.

Nineteen firefighters from the Rural Fire Service battled the fire amid "strong and gusty north-westerly winds" and temperatures above 38 degrees, assisted by helicopters and Fire and Rescue NSW. A large air tanker flew to the area from Victoria to "make a drop" on the bushfires, Mr Allan said.

A southerly change is sweeping through the area, pushing the fire in a notherly direction which may pose risks to other properties in the region.

"The risk is that the side of the fire could become the frontline [with the southerly change]," Mr Allan said.

"It's pretty unpredictable, given these conditions, but the crews are working fast and hard to contain it."

Residents north of the Bega River have been advised to head in a northern direction towards Bermagui. Campers at campgrounds to the north have been relocated where it is safe to do so.

An evacuation centre has been established at the Bega Showground.

The fire was just one of 26 grass and bush fires burning in NSW on Sunday, with 12 burning out of control at 8pm, as temperatures soared above 40 degrees through the day across the state. More than half of the state was under a total fire ban on Sunday.

A fire which burnt 300 hectares near Goulburn was downgraded on Sunday night to an "advice level" as conditions ease.

Meanwhile, in Victoria, homes were destroyed as firefighters battling fierce winds worked to contain a cluster of fires burning out of control in the state's south-west.