The situation with a major fire at Girilambone has improved with the blaze currently under tenuous control, however a second fire to the north is yet to be contained.

Since it started on Booramugga Road, Girilambone on Saturday afternoon 4 March, the fire has burnt out 3300 hectares, blocking the Mitchell Highway and cutting power to a massive area around Bourke.

However the NSW Rural Fire Service (NSW RFS) are cautiously optimistic.

"It has stayed within containment since yesterday and fire-fighters are in mop-up stage with that fire," said NSW RFS Public Information Officer Shellie Smyth.

"However that could change if there is a change in the wind or an increase in temperature."

The Mitchell Highway re-opened yesterday afternoon and power has also been restored to customers affected by the outage.

Just north of the Girilambone fire at Glenariff Station, between Coolabah and Byrock, a second fire is still growing.

"The fire-fighters are working really hard and we've got aircraft and heavy plant working out there as well," Ms Smyth said.

"It has burned more than 4900 hectares in what is pretty difficult terrain but there are no properties under threat at this time."

Footage from the Girilambone fireground courtesy Nyngan RFS HQ brigade.

https://fb.watch/j7x4eOF7rk/

"We've got lots of resources coming in to provide some respite to our local fire-fighters," she said.

The first fifty fresh fire-fighters will be arriving in Nyngan today from the Hunter Valley, and will be part of an 80 strong crew amassing over the next couple of days.

A Base Camp is being established at Nyngan Showground and two shipping containers with infrastructure such as kitchens, bathrooms and accommodation will be on site and set up today.

"There's a few more trucks to come," Ms Smyth said. "We try to make the camp as comfortable as possible for our fire=-fighters."

"Obviously the community of Nyngan will see an increased RFS presence in the area," she said.

"With the wind people will see smoke over a large area of the western plains. If you do see an unattended fire please call 000 immediately."

A smaller fire at Cable Downs Stations near Cobar which burnt out 868 hectares is now under control.