Sydney to swelter through more heatwave conditions as nine regions face total fire bans

Authorities are on alert with extreme fire danger forecast across a large part of NSW, with warnings that conditions could worsen, as total fire bans are in place across nine regions across the state.

Temperatures are expected to soar higher than yesterday, with Penrith expected to hit 41 degrees and 39 degrees forecast in Sydney's CBD.

The Bureau of Meteorology has said that the hot and dry conditions mixed with strong west to northwesterly winds are expected to bring increased fire dangers to NSW's central and northern regions.

A west to southwesterly wind change is set to move through later in the afternoon and evening.

"Today we're going to see extreme conditions across the state with, again, really strong winds, high temperatures and low humidity," NSW Rural Fire Service Commissioner Trent Curtin said.

"So we're really concerned going into today with fires that might get up and running quickly."

"We've had some major fires burning up in the Hunter area that have been growing yesterday and overnight."

There are fears that up to four homes have been lost in a bushfire that began on Thursday on NSW's Mid North Coast in Bulahdelah.

The RFS has said that it is currently too dangerous to assess the damage of the blaze, however, they are expected to do so later this morning.

Overnight conditions in that area have not been ideal, so officials have warned that the fire could potentially ramp up again today.

"We've got extreme conditions in seven areas and total fire bans in nine areas," Curtin said.

Extreme fire danger is forecast in the Greater Hunter, Greater Sydney Region, Illawarra/Shoalhaven, Central Ranges, North Western, Upper Central West Plains and Lower Central West Plains.

Severe heatwave warnings are in place for the Hunter, Metropolitan, Illawarra, South Coast, Central Tablelands and Southern Tablelands regions.

"So right through Sydney, Illawarra, Newcastle and through the central parts of the state, we've got extreme fire danger, but we've got high fire danger right across the state."

This afternoon is expected to bring strong winds before a cooler change is forecast to come later this weekend.

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