Tony Abbott is on standby with his local fire brigade as NSW nervously awaits the outbreak of new bushfires.
The federal opposition leader flew back from a political engagement in Brisbane on Tuesday morning to join forces with Davidson Rural Fire Brigade, on Sydney's bushfire-prone north shore.
"I'm now on my way to Sydney to be on standby with my local fire brigade," Mr Abbott tweeted.
"Important to follow fire warnings and advice today."
Mr Abbott has been a volunteer with his local brigade since 2000, served as its deputy captain before becoming opposition leader in 2009 and has previously been directly involved with fighting fires.
There were no bushfires reported in the Davidson Rural Fire Brigade's area on Tuesday morning but a Rural Fire Service spokesman said it was an area of real concern.
"All those highly populated areas around the Sydney outskirts, and the northern (Sydney) area in particular - that is an area of concern," the spokesman told AAP.
It was not immediately clear how long Mr Abbott will remain on standby or whether he has cancelled any political engagements on Wednesday.
It comes as NSW remains on high alert for the outbreak of new bushfires, with temperatures predicted to rise well above 40 degrees across much of the state.
More than 20 uncontained fires were burning in NSW on Tuesday morning, with one blaze at Carlaminda impacting homes.
The RFS said a cool change was forecast to sweep across Sydney late on Tuesday night or early Wednesday morning, bringing relief for residents and potentially reducing the danger of more fires.
"The temperatures will really back off, but it all depends on how we go over the next 12 hours," the RFS spokesman added.