The NSW Rural Fire Service has declared a total fire ban for the Greater Hunter on Tuesday, due to forecast hot and windy conditions.
A top of 42 degrees is predicted for Cessnock, and the mercury is expected to reach 41 degrees in Maitland and 38 in Dungog.
The Little L Complex fire near Wollombi - which reached emergency level on Friday - continues to burn at advice level, and is now more than 65,000 hectares in size.
It has merged with the Gospers Mountain fire in the Wollemi National Park (300,000 ha), the Paddock Run blaze near Putty (17,000 ha), the Kerry Ridge fire in the Muswellbrook LGA (36,000 ha) to create a mega-fire with a boundary of more than 60 kilometres.
Back burning operations are continuing as conditions allow in the Boree Valley Road area.
People in Paynes Crossing, Wollombi and Laguna are urged to monitor conditions.
East of Wollombi, the Crumps Road fire in Corrabare State Forest has reached 5000 hectares and is being controlled.
Back burning operations have begun on the southern flank of the fire along Cedar Ridge Track.
Residents of Narone Creek, Congewai and Sweetmans Creek are advised to monitor conditions, as the fire expected to spread to the east and north on Tuesday after a southerly change.
The Owendale fire in the Pokolbin State Forest, near Broke has burned through 1000 hectares and is at advice level.
Fires off Leggetts Drive, Pelaw Main (423 ha) and Martins Creek Road, Paterson (376 ha) remain at Advice level, after reaching emergency status last week.
Under severe fire conditions, the RFS urges residents to follow their bushfire survival plans and remain vigilant.