[Rating: 0]
Emergency blaze northwest of Sydney

The heavy smoke that is smothering Sydney in forecast to stay into the weekend. Courtesy: News Yahoo

An emergency warning has been issued for a bushfire northwest of Sydney as authorities say heavy smoke smothering the city is forecast to linger into the weekend.

Firefighters faced another tough day of windy and dry conditions on Wednesday with total fire bans in place for the greater Hunter, the northern slopes and northwestern regions of the state.

An emergency warning was issued for the 230,000-hectare Gospers Mountain blaze in the Wollemi National Park after 4pm on Wednesday.

The nearby Three Mile fire – which has burned through 5800 hectares – was at “watch and act” alert level.

“Properties are under threat in the Colo Heights area,” the NSW Rural Fire Service warned.

“Wisemans Ferry Road is closed from the ferry east to Mill Creek.”

The RFS on Wednesday said the “heavy smoke” would be noticeable in Sydney for several days.

“Very heavy smoke is affecting the Sydney area. It is being blown from large fires near Warragamba Dam,” the service said in a statement.

“Smoke is also affecting areas including the north coast, Hawkesbury, Wollondilly, Queanbeyan and Shoalhaven areas.”

The Bureau of Meteorology said the smoke would stick around until Saturday.

Lingering smoke could be “unhealthy for sensitive people, and could cause symptoms, especially in people with heart or lung disease”, the state’s environment department said.

Air quality levels were hazardous in parts of Sydney on Wednesday morning.

There were 116 fires burning across the state on Wednesday with 60 uncontained. There are more than 2200 firefighters in the field.

Firefighters worked through Tuesday night to protect houses from the 47,000-hectare Currowan blaze north of Batemans Bay on the South Coast.

“Firefighters overnight worked to protect a number of properties in coastal communities,” the RFS said.

“Easing conditions have seen the threat to homes reduced.”

The Currowan blaze – which has destroyed at least one home – has been downgraded to “watch and act”.