Several remote villages on the NSW mid coast may be impacted by a bushfire burning in the region, firefighters have warned.

Four fires burning in an easterly direction in the Greater Taree, Gloucester, Wauchope and Great Lakes areas are challenging crews on Sunday morning.
Residents have been advised to monitor the situation closely and implement their bushfire survival plans.

"With extreme fire conditions expected in this area today, fires could spread rapidly and may impact small remote villages and roads in the area," the NSW Rural Fire Service said in its watch and act advice message.

Authorities have also warned local roads may be closed at short notice.

Large swathes of NSW are in the grips of unprecedented fire danger conditions, with senior firefighters describing the conditions as "off the conventional scale".

The Bureau of Meteorology rated the fire danger in the Greater Hunter, Central Ranges and North Western regions as "catastrophic".