EARLIER: NSW Rural Fire Service crews were kept busy with several fires that broke out in the Pilliga Nature Reserve on Thursday.

A large firefighting aircraft was sent to drop retardant at the site, and an air base was set up at Dubbo airport with members of the Orana Aviation Support Group helping reload retardant for the large air tanker that worked on the fires.

The fires, which were near Coonabarabran, were believed to have been sparked by lightning.

By Thursday afternoon the Newell Highway was closed in both directions between the Oxley Highway and Kamilaroi Highway due to a bushfire at Dandry, north of Coonabarabran.

It came after 50 Rural Fire Service (RFS) firefighters battled a blaze that broke out south of Dubbo on Wednesday.

Orana RFS team leader Superintendent Lyndon Wieland said crews responded to reports of a fire on Days Road, near the Newell Highway, 28km south of Dubbo about 6pm .

"When they arrived they found some scrubby country well alight so access proved very difficult at first," he said.

"There were about 50 people on the ground and they managed to have it contained by about 12.30am (Thursday)."

Two fixed-wing water bombers and a bulldozer were also used to fight the fire.

On Thursday morning, a helicopter was also deployed to drop water on hotspots in the centre of the fireground that crews were not able to access because of the danger posed by falling trees, Superintendent Wieland said.

Fencing in the area that was mostly private property was destroyed but there were no reports of any other infrastructure being damaged, nor were there any reports of injury.

"At one stage an adjoining property came under threat but we were able to stop that," Superintendent Wieland said.

He said while the cause of the fire was yet to be confirmed, there was no evidence to suggest it was deliberately lit. The fire burnt out about 15 hectares.

While the outside temperatures were high in the region on Wednesday afternoon, there was at least one meteorological factor the firefighters had going for them, according to Superintendent Wieland.

"It was about 42 degrees, but the winds were only gusting about 20km/h.

"We were lucky, that's not too bad.

"If we had the winds we had the day before that fire would still be running."