'Like an eclipse': Eerie scenes as towns turn red

The “unprecedented” bushfire threat continues into the night as winds of up to 130km/h fuels more than 20 emergency warning fires across Australia’s southeast.

There are 12 emergency fire warnings across NSW, including an out-of-control bushfire in between two giant fires on at the NSW-Victoria border which is likely to lead to a mega blaze spanning more than 300,000 hectares.

A dangerous southerly arrived in Victoria’s east early afternoon and is now fuelling fires as it moves along the east coast through NSW.

“We are in for a long night,” NSW Premier Gladys Berejiklian told reporters shortly after 4.30pm.

Winds of 128km/h were recorded at Cabramurra about 6pm where the now 230,000-hectare Dunns Road fire continues to spread.

Hours earlier it was 145,000 hectares in size.

There were once again apocalyptic scenes in towns in bushfire-affected areas, with many images on social media revealing a quick descent into darkness.

Images shared by Mallacoota resident Brendan, who has documented the plight of the coastal town since fires ripped through it earlier this week, showed the skies returning to a dark red with limited visibility.

There were similar scenes in a handful of towns moving along NSW’s south coast.

Photos from Eden, Merimbula and Bega showed the towns in complete darkness.

At about 4pm, Narooma on NSW’s far south coast, was lit up with an orange skyline, peppered with burning leaves.

The Badja Forest Road fire, roughly 200,000 hectares, burns perilously close to the west of Narooma.

Fears two fires in NSW, VIC could merge

A huge threat facing exhausted crews is the potential for the 128,000-hectare Green Valley fire at Corryong in Victoria to merge with the Dunns Road fire roughly 70km north in NSW.

The Dunns Road fire around Tumbarumba has breached the Snowy Mountains Highway - it is too late to leave for residents in Adelong and surrounding towns.

Nestled in between the two fires is the out-of-control, 400-hectare East Ournie Creek fire which has been upgraded to emergency warning.

With the introduction of strong winds, which were predicted to reach 100km/h, and paired with temperatures well into the 40s, there is real concern the fires will combine.

NSW RFS Commissioner Shane Fitzsimmons said some crews were forced to retreat from tackling the fires he called a “conflagration” as conditions worsened with a wind change.

There are strong fears dry lightning storms and travelling embers will also start more fires.

The Currowan fire and Clyde Mountain fire, which surround the coastal towns of Batemans Bay and Ulladulla where thousands of tourists fled in the previous two days, are at emergency warning level and span a combined 345,000 hectares.

Some 30,000 customers in the Batemans Bay and Moruya regions have lost power due to bushfire affecting infrastructure, Essential Energy said on Saturday afternoon.

The RFS says residents in Bermagui, Regatta Point, Wallaga Lake and Wallaga Lake Heights should monitor conditions "and know what you will do if the fire threatens".

Hospitals in Batlow, Pambula and Tumut were evacuated as were healthcare facilities in Tumbarumba and Delegate.

Worst is still to come, RFS says

RFS commissioner Shane Fitzsimmons says the worst of the weather is yet to eventuate.

"It's a very dangerous few hours given the amount of emergency alerts that are out there," he told reporters before 5pm.

Some 3600 firefighters are on the ground battling blazes while hundreds of others have been pre-positioned to tackle any new outbreaks.

Mr Fitzsimmons said some large fires were generating their own thunderstorms which could generate cyclonic-type winds.

In some areas, firefighters had been withdrawn for their own safety.

The southerly is expected to reach Sydney about midnight.

Emergency alerts rocket in Victoria

Fourteen emergency alerts are now in place in Victoria as the danger in the state’s fire-ravaged east worsens.

"Omeo Valley is under direct attack – which is causing significant fire spread around Omeo and Ensay," the Department of Environment Land Water and Planning posted on Facebook at 2pm.

"Firefighters are actively protecting life critical infrastructure and community assets in this area.

"Charred leaves have started to fall into Swifts Creek."

An emergency alert was issued for Omeo and surrounding areas about 12.40pm and people are being told it is too late to leave and seek shelter.

Authorities are trying to get into 18 isolated communities in East Gippsland and the northeast via military helicopter to check on their welfare and provide satellite phones and provisions, but so far access has only been achieved at two.

Across the fire zone in East Gippsland, there's usually a population of about 100,000 people and police estimate 60 to 70 per cent of people have now left.

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Anyone making late decisions to leave needed to check the fire conditions, Emergency Management Commissioner Andrew Crisp said.

The Princes Highway has been closed towards NSW from Lakes Entrance.

There are currently 21 people across East Gippsland that remain unaccounted for.

Deaths confirmed in South Australia

Earlier on Saturday, authorities confirmed the deaths of two people attempting to flee an out-of-control fire on Kangaroo Island.

The fire, which has so far burnt through 100,000 hectares, is yet to be controlled.

Premier Steven Marshall said the deaths were tragic news.

"Our hearts go out to the families of those people who have been affected," he said.

"It really does reiterate the very important message that people listen to the alerts. This a very dangerous situation on Kangaroo Island."

Significant property losses are expected from the fire with major damage to tourism and other infrastructure also likely.

About 500 firefighters will continue to battle the blaze over the weekend, with crews and other resources brought in from the SA mainland.

So far during this year’s national bushfire season, 22 lives have been lost.

More than 1500 homes have been destroyed across the country.

Records tumble as NSW swelters in heat

Canberra and the western Sydney suburb of Penrith on Saturday broke temperature records that had stood for 80 years.

The mercury climbed to 43.6C in Canberra and 48.9C in Penrith - a new record for the Sydney basin beating the previous mark of 47.8C recorded in Richmond in 1939.

The previous Canberra record was 42.8C at the now-closed Acton observation site in 1939.

With AAP

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