The Sydney Harbour fireworks will ring in 2020 despite the closure of popular vantage points, and political and community opposition.

The NSW Rural Fire Service on Monday granted the fireworks - seen by one billion people across the world - an exemption from a total fire ban.

Temperatures around the state are expected to peak on Tuesday, with forecasts of more than 40C across western Sydney and in regional NSW.

NSW Deputy Premier John Barilaro on Monday called for the fireworks to be scrapped and funds redirected to drought and bushfire relief, echoing calls from a petition signed by more than 275,000 people.

City of Sydney Lord Mayor Clover Moore on Tuesday reiterated much of the event's budget has already been allocated and the event generates $130 million for the NSW economy. The council has donated $620,000 to bushfire and drought-affected communities.

"The compelling issue here is climate change," she told reporters.

"Australia is burning - our national parks and our native animals are being decimated and our communities are being devastated. People have lost homes, people have died, firefighters have been killed defending communities.

"As the driest continent on earth we're at the forefront of accelerating global warming. What is happening is a wake up call for our governments to start making effective contributions to reducing global emissions."

The lord mayor said climate change action has been the council's top priority since 2008 and pointed to its movement on emissions reduction.

"Cities around the world are doing their bit to address global warming - it's our national governments that are failing us," Ms Moore said.

Federal energy minister Angus Taylor wrote an opinion piece in The Australian newspaper on Tuesday arguing that Australia's emissions reduction performance was something for which to be proud.

However Ms Moore said Mr Taylor was "the minister responsible for addressing global warming, and he has failed".

At 10am smoke haze had already settled on Sydney Harbour, which Ms Moore said was a message to the government to "start getting their act together and start taking effective action on accelerating global warming".

Federal Labor leader Anthony Albanese on Tuesday said it was problematic the foreshore firework display was proceeding.

"I understand how important the fireworks are for our economy, but I just think at a time like this - I'm not in a position to judge - but I think that it's really problematic that it's going ahead," Mr Albanese told reporters in Brisbane.

Premier Gladys Berejiklian has admitted to "mixed feelings" about the fireworks display in Sydney amid elevated bushfire risk and the death of a volunteer firefighter near the NSW-Victoria border.

Fire danger ratings for Sydney, Newcastle and the state's south - where several emergency-level blazes are burning - range from severe to extreme.

Ms Berejiklian on Tuesday told reporters the death of expectant father Samuel McPaul on the Green Valley fire ground at Jingellic - where a "fire tornado" lifted and flipped his fire truck - would cast a pall over festivities.

Mr McPaul is the third volunteer firefighter to die this bushfire season.

"Many of us have mixed feelings about this evening but the important thing we take out of this is that we're resilient as a state," Ms Berejiklian said.

While the harbour will have fireworks, revellers will be unable to use the forested Balls Head Reserve or Bradleys Head as vantage points due to the fire risk.