NSW bushfire emergencies downgraded

Firefighters have gained the upper hand on two NSW fires which prompted emergency warnings after they broke containment lines and began burning out of control.

Crews face a long night keeping the fires under control before winds and hot weather put them on the back foot again on Monday.

A fire at Ellangowan, south west of Ballina, broke containment lines and jumped a creek at about 4.30pm on Sunday, prompting an emergency warning.

It was the second fire of the day to reach emergency level after powerful winds hit the state, whipping up flames.

The blaze burned toward isolated rural properties and emergency warnings told residents it was too late to leave.

They were told to seek shelter as the 2000-hectare fire bore down but conditions eased and firefighters regained control.

A few hours earlier the NSW Rural Fire Service had reined in another out of control fire at Salt Ash, just north of Newcastle.

It's believed a caravan may have been destroyed in the fire but crews are yet to confirm, RFS Deputy Commissioner Rob Rogers said.

The two blazes are currently at watch and act level and crews will spend the night blacking out flares in the scorched bush.

A very high fire danger remains in place for NSW's northeast as well as the greater Sydney region with Monday's forecast likely bring little relief.

"Those strong winds are going to keep fanning those fires," Mr Rogers told the Seven Network on Sunday.

"We're looking at those winds extending into around Wednesday."

Nearly 20 buildings, mostly outbuildings, have been destroyed by fires since late last week.

A 14-year-old boy and a 52-year-old man were separately charged over the last week after fires were allegedly sparked deliberately near Casino in the state's north.

On Saturday the fire allegedly linked to the teenage boy razed 175 hectares of land, damaged a fire truck and triggered evacuation preparations of nearby Tabulam township.

On Friday, helicopter pilot Allan Tull died while water-bombing a fire west of Ulladulla, on the NSW south coast.

It's believed the 1994 Kawasaki helicopter's water bucket became stuck in trees, pulling the chopper down.