The outbreak is burning in national park in Bungonia Gorge but spotting along Caoura Road at Tallong.

RFS operations officer Lachlan Gilchrist said the fire had proved a challenge over the past 24 to 48 hours and was still being controlled. It has burnt out an estimated two hectares.

"We have aviation resources that will fly out today," he said earlier on Friday.

"Those resources have been stretched across the state and visibility from the smoke has also been a challenge," he said.

Four crews from Southern Tablelands zone are also on the ground today. Mr Gilchrist was confident that was sufficient given its size.

But it remains a concern given Saturday's looming conditions.

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Mr Gilchrist said they could be as bad, "if not worse" than Tuesday's extreme temperature and strong winds that fuelled firestorms through south coast communities.

"This (tomorrow) is looking even more substantial and we're expecting a big wind shift in the late afternoon that looks even stronger than earlier this week."

Predominantly northwest winds are expected, gusting at between 30 to 70km/h, RFS zone manager Peter Alley said during the week. This would push the Tallong outbreak back down into the gorge and not cause serious problems, he speculated.

But Mr Gilchrist said the southeast wind shift in the afternoon could see the Tallong and nearby Bungonia fires break containment lines.

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He reissued a warning to those communities, as well as Windellama and Marulan to monitor conditions, enact bushfire plans and leave if they were unable to defend their properties. The RFS doorknocked Tallong properties, including those along Caoura Road, reinforcing this message earlier in the week.

Some residents have already left. One said there was insufficient water to fight it if the fire rushed towards the village.

But Mr Gilchrist responded that if that were the case, water wouldn't be the issue.

"We have bulk water carriers and they are available to us for containment work and backburning but I stress that under these conditions, water doesn't matter because we won't be able to fight it," he said.

"Direct attack is not an option; no property is defendable."

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The fire rating was likely to be extreme on Saturday, with 40-degree plus temperatures, Mr Alley said earlier this week.

The northwest wind is also expected to have a "significant impact on the Green Wattle fire around Wombeyan Caves.

The northwest wind is also expected to have a "significant impact on the Green Wattle fire around Wombeyan Caves, which has so far burnt 264,665 hectares.

The Currowan fire stood at 262,274ha at 2pm Friday.

Southern Tablelands RFS will hold a meeting on Friday, January 3, to update the Taralga community on the Green Wattle fire.

Operations officer Lachlan Gilchrist said the meeting at the fireshed in Orchard Street at 7pm would inform the community on what to expect over the weekend, given impending "challenging conditions."

"Northwest winds will have a significant impact on the fire, especially around the Wombeyan Caves area. We are looking at severe winds coming through tomorrow morning and during the day," Mr Gilchrist said.

"These winds will push the fire towards Bannaby Road and later in the afternoon, expected southeast winds will turn it around back on its self. We expect tomorrow to be a very difficult and challenging day."

Earlier this week, the Green Wattle Creek blaze flared up around the Wombeyan area. Dianna Bisset, who owns wildlife sanctaury 'Rocklily Wombats' with husband Warwick, described a "firestorm" coming over the hill in front of them.

"It was 360-degree firefighting," she said.

The couple managed to save their home and animals but Mrs Bisset believed up to six other structures could have been destroyed. The RFS is still undertaking a property assessment.

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The meeting will be held in the fireshed in Orchard Street at 7pm.

Fire authorities are expecting a very challenging weekend with 40 plus temperatures and predominantly northwest winds.

Meantime, a fire off Oallen Ford Road continues to "track along" in inhospitable country off Oallen Ford Road, 8km south of Bungonia.

Mr Gilchrist said it was largely burning in national park in the southeast and open country in the northeast and northwest.

"We expect it will merge with the Currowan fire but there are no properties in the area," he said.

However, with a number of uncontrolled bushfires around, he said people needed to remain vigilant about the threat.

The fire stands at 808 hectares. It started on Saturday, December 28.

This morning, Mr Gilchrist said the Currowan fire had not moved greatly in the Southern Tablelands region. While there was an outbreak on another spot over the Shoalhaven at Erie Park just after noon, it was quickly controlled. At 4.30pm he said the northwest winds were still largely pushing the Currowan fire onto itself

But people should not be complacent.

"These are as much weather systems as fire systems," Mr Gilchrist said.

"I think people have taken the weekend's message to leave early. If it was a flash flood, they wouldn't be sitting on the riverbank. As the south coast fire demonstrated, it can turn very quickly."