Map reveals 'massive' 6000km fire threat facing northern NSW

An alarming map has revealed the devastating threat facing communities in NSW as bushfires continue to rage.

The NSW Rural Fire Service reiterated the “massive” task facing firefighters with a map of the state’s north showing affected areas, with several fires expected to join up in coming days.

“All up, there's more than 6000km of fire edge to deal with – the equivalent of flying from Sydney to Perth... and back again,” the RFS said.

Further south, firefighters battled an emergency warning blaze northwest of Sydney overnight, with haze from it and other fires throughout the state expected to blanket the city for the second day in a row.

The 146,000-hectare bushfire at Gospers Mountain was upgraded to an emergency warning level on Tuesday night, with residents living in the Colo Heights area told it was too late to leave. A southerly change eased conditions overnight and the fire was downgraded to advice level on Wednesday morning.

It is just one of 54 fires burning across the state on Wednesday morning, 22 of which are yet to be contained.

Queensland bushfires to be fuelled by extreme heat

Firefighters are bracing for heatwave conditions across Queensland's fire zones, sending temperatures and the danger level soaring.

The mercury is expected to reach the mid to high 30s near some of the major fires on Wednesday, while parts of the state's interior are expected to hit 40 degrees.

Queensland Fire and Emergency Services Acting Commissioner Mike Wassing fears the bushfire emergency will push into next year because there is no prospect of significant rain.

The best crews can do is strengthen containment lines and be ready when the weather worsens.

Seventy fires are burning across Queensland in the second week of the state's bushfire crisis, which has burnt out 174,000 hectares.

In total, 16 homes have been lost in the recent fires but that figure will rise after firefighters confirmed homes were lost in the Pechey fire north of Toowoomba.

Aerial footage revealed structural damage from the large Pechey blaze, which forced evacuations from the town of Crows Nest on Monday.

"We believe we probably have five structures in there, and maybe more," Queensland Fire and Emergency Services Deputy Commissioner Mark Roche said.

"We've been able to get some aerial footage but we won't know until we get in on the ground ... trees are still burning."

Residents who fled Crows Nest were allowed to return home after an emergency alert was downgraded.

Toowoomba Region Mayor Paul Antonio is fearful of the weather conditions ahead, saying his community is facing dangerous times.

Water levels a concern

Residents are on water restrictions while work continues to restore power to pumps at the city's main reservoir after it was cut by fire.

Fires of primary concern in the state include the Pechey blaze, a cluster of fires in the Border Ranges region, from Cunninghams Gap to Mount Barney and Mount Lindsay, and one on Moreton Island.

Meanwhile, combined dam levels in southeast Queensland have dropped to their lowest since 2010.

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The drop has resulted in the Tugun desalination plant on the Gold Coast being ramped up to full capacity.

SEQ Water is urging residents to start voluntarily conserving water.

It says mandatory restrictions will not be enforced until the combined dam level drops by another 10 per cent, to 50 per cent.

South Australia to face ‘catastrophic’ fire danger

Catastrophic fire danger conditions have been declared for much of South Australia for Wednesday, with more than 100 schools closed and at-risk residents told to leave their homes.

The Bureau of Meteorology has forecast a maximum 42 for Adelaide, while the mercury is expected to reach 45 at Murray Bridge, 44 at Renmark, Port Augusta, Port Lincoln and Whyalla, and 43 at Port Pirie.

Seven districts were declared catastrophic fire danger zones on Wednesday – including the Mount Lofty Ranges and Mid North near Adelaide – while two were rated 'extreme' and six 'severe'.

In regions affected by catastrophic danger, national parks and reserves will be closed as well as schools with R1 or R2 bushfire risk ratings.

The CFS advised people living near bushland in catastrophic fire ban districts to leave late Tuesday or early Wednesday morning.

They warned a bushfire could not be controlled in such conditions.

A total fire ban will be in place across the state.

Bureau of Meteorology acting supervising meteorologist Paul Lainio said several November heat records could fall on Wednesday.

"Wednesday's forecast for Adelaide at this stage is 42C, just shy of West Terrace's hottest November day in 1962 on November 30 of 42.7C," he said.

"Across South Australia, temperatures on Wednesday will peak 8-18C above average ahead of a cold front that's accompanied with strong winds.

"Those towns that may break temperature records are in the south and west of the state and include Victor Harbor, Nuriootpa, Keith, Naracoorte, Murray Bridge and Robe and Lameroo."

Victoria heating up for early summer

Melbourne will experience two days of early summer as it begins to heat up on Wednesday, before hitting one of its hottest November days on record with temperatures forecast to hit 39 on Thursday. On Wednesday evening temperatures will be in the high 20s to low 30s.

"For Melbourne, the last time it reached 39 degrees was in 2012 and the all time record for November is just over 40," Bureau of Meteorology senior meteorologist Richard Carlyon said.

"Normally at this time of the year we start to see some summery weather with temperatures reaching the mid 30 degrees, but it is unusual to see them into the high 30s."

Temperatures are expected to be milder along the bayside, with Geelong and the Mornington Peninsula not reaching over 30 degrees.

This sudden heat, however, will be especially tough in the northern part of Victoria, where northerly winds will leave temperatures well over 40 both on Wednesday and Thursday.

These scorching days affecting all of Victoria prompted the CFA to declare a total fire ban for the Mallee region on Wednesday.

The ban is forecast to be lifted by Thursday.

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