Police were called to the area last night in case an evacuation of Newcastle Airport was needed.

The fire followed a night where Novocastrians sweated through a November record 23-degree heat and awoke to a haze one-tenth as thick as the dust storm in September.

Yesterday's dust peaked at 975 micrograms per cubic metre at 10am, the weather bureau's Chris Eiser said.

The city average is about 20, but the haze was nowhere near September's 10,000.

The Rural Fire Service said there was no immediate threat to property in last night's fire.

It was burning on the northern side of Cabbage Tree Road and was behind containment lines.

Firefighters were expected to strengthen the lines overnight and conduct backburning south of Richardson Road.

Newcastle Airport aviation services manager Graham Giddey said the runway reopened about 8.30pm after being closed about 5pm because of extensive smoke in the area.

The fire burnt to the fence at the north-west end of the RAAF base and an evacuation of the airport had been considered, he said.

"We had plans in place, the police were in here to help, but there was no real threat to the terminal," Mr Giddey said.

The fire also burnt around properties at Barrie Close, off Cabbage Tree Road.

In yesterday's haze, Newcastle resident Brenden Wood said visibility was down to 500 metres in his street.

"It's got worse in the last half hour," he said. "It's the second most dusty day of the year. The dust is yellow and golden."

Mr Eiser said the dust was yellow because it was thinner than in September.

"It's worked its way through north-west Sydney and it's hit the Lower Hunter the hardest," Mr Eiser said.

"It's a widespread event that's brought dust from South Australia. It's happened a few times recently."

The Hunter's hazy wake-up capped a scorching November with record average highs for Newcastle and Scone of 29 and 32 degrees respectively.

November 20's 44 was Cessnock's hottest spring day ever. with AAP