More than 60 bushfires are still burning across NSW, with widespread very high fire danger and hazy Sydney conditions set to stay.
While there are no total fire bans in place for Friday the Rural Fire Service NSW says warm weather is set to continue, with nine regions - including the ACT and entire northern coast - at "very high" fire danger.
Greater Sydney is at "high" fire danger but is also grappling with heavy smoke blanketing the city from the nearby Gospers Mountain fire in the Hawkesbury, which has burned through more than 170,000 hectares.
A dust storm coming in from South Australia would also reduce visibility.
The RFS said haze around Sydney would dissipate throughout the day but NSW air quality indexes on Friday morning deemed Sydney's northwest and southwest regions "hazardous" for air pollution. Sydney's east was deemed between "very poor" and "hazardous" quality.
The Lower and Upper Hunter regions were also enduring hazardous air quality.
"Once again over the weekend, because of northeasterly winds, we could actually see that smoke come in again," RFS spokesperson Ben Shepherd told the Seven Network on Friday morning.
"Until such time that we get a big clearing event, we're going to have this smoke settling over Sydney each and every morning."
The RFS announced on Thursday that 612 homes had so far been lost in the state's bushfires, including 530 in the past fortnight alone.
The fires have also claimed six lives this bushfire season.
A total of 62 fires were burning at 9pm on Thursday around NSW, with 24 uncontained and hundreds of firefighters still in the field.
Australian Associated Press