NSW is facing widespread severe bushfire danger as predicted hot winds blowing in from the south present yet more challenging conditions for firefighters.
Rural Fire Service NSW Commissioner Shane Fitzsimmons said a weather system coming in from South Australia will bring hot easterly winds on Thursday.
"We know over the coming days, particularly tomorrow, we're expecting again widespread very high to severe conditions," Mr Fitzsimmons told ABC TV.
"This time, the indications are (it will be) the southern half of NSW with some of the more widespread, worst conditions. We've got a long way to go yet."
People have been urged to have their fire plans prepared and to know what to do if they come under threat.
There are 12 total fire bans in place across the state.
A severe fire danger rating is in place for 10 areas, including Illawarra/Shoalhaven, North Western and the Southern Riverina.
"Now is the time to have a discussion with your family and know what you'll do if fire threatens," the Rural Fire Service tweeted.
Most fires are at advice level on Wednesday evening.
However, alerts have been elevated to watch and act for a near-20,000 hectare blaze at Ebor near Armidale, and a bushfire at Myall Creek Road in Bora Ridge, southeast of Casino which has consumed more than 30,000 hectares.
The Rural Fire Service warned there will be "broad areas of very high and severe fire danger" on Thursday.
There were 50 fires across the state on Wednesday afternoon, 24 of which were uncontained.
More than 1000 firefighters remain in the field.
Sydney's air quality, which has deteriorated in a smoky haze in recent days, is unlikely to improve anytime soon as the fires continue, the Bureau of Meteorology said.
There are also concerns that weekend thunderstorms, which won't bring much rain, could see lightning strikes ignite additional fires.
Six lives and 577 homes have been lost to date this fire season, with more than 420 homes lost in the past fortnight.
Police, meanwhile, told reporters on Wednesday that legal action had been taken against 54 people since August for bushfire-related offences.
Acting Assistant Commissioner Stuart Smith said those offences ranged from total fire ban breaches to deliberately lighting fires endangering life.
Australian Associated Press