WORSENING conditions, coupled with high temperatures, have forced the NSW Rural Fire Service (NSW RFS) to lift the level of the Kerry Ridge bushfire to "emergency warning" on Thursday evening.
The blaze, located within the Muswellbrook, Singleton and Mid-Western LGAs, is burning in the Wollemi National Park, Putty State Forest and Coricudgy State Forest.
It's now more than 81,000 hectares in size and is out of control.
However, 40-degree heat on December 19 intensified the situation for local firefighters.
"While the fire continues to burn in the national park and neighbouring state forests, it's also increasing in the area of Olinda and Nullo Mountain," a NSW RFS spokesperson said.
"Embers are starting spot fires ahead of the main fire front.
"It is continuing to spread slowly toward isolated rural properties north of The Ovens and Bin Ben, as well as areas of Gum Tree Hole and Kindarun.
"Due to the rugged terrain, this fire continues to burn to the north.
"The Paddock Run fire is burning to the south in the Kindarun area, too.
"Unfortunately, these fires may merge over the coming days as the conditions are forecast to deteriorate again on Saturday."
Meanwhile, NSW Premier Gladys Berejiklian announced a State of Emergency on Thursday.
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