NSW woman burned at Hunter Valley party

A 24-year-old woman will be flown to the burns unit of the Royal North Shore Hospital after suffering horrific burns during a party in the Hunter Valley.

A bushfire has broken out northwest of Hobart in Tasmania's south as the mercury edges towards 30C. (AAP)

A woman has suffered horrific burns to half of her body during a backyard party in the NSW Hunter Valley, police say.

The 24-year-old was with a dozen people sitting around a small campfire at the Morpeth property just after midnight on Sunday when a man poured accelerant on the fire to rekindle it.

The victim was taken to the John Hunter Hospital in a stable condition and will be flown to the burns unit of the Royal North Shore Hospital on Sunday, while three other people were treated for minor burns.