Northland's fire authority is warning locals not to light any outdoor fires because the land is tinder-dry.

Photo: Supplied

A local landowner could face prosecution and a fine of up to $300,000 for a fire that was deliberately set a few days ago.

Photo: Supplied / Fire and Emergency

The landowner was burning off slash - forestry waste - without a permit.

It followed two serious wildfires in the Bay of Islands last week and another near Kaikohe that burned off more than 60 hectares of land.

A complete fire ban has been imposed in Northland, which has had no rain since before Christmas. The region's deputy chief rural fire officer, Rory Renwick, said even the smallest fire could get out of hand easily.

You can stay up to date with fire weather here.

Fire and Emergency also advises using the fire season status and the Check It's Alright website.

"We are facing a higher fire danger and particularly when it's like this, fires that were lit several days ago - larger fires - can get up and go again because they are still smouldering," he said.

Some larger fires could pop up again weeks or months later as conditions got drier, he said.

He told Morning Report people should follow the rules, otherwise fines would be imposed.

Mr Renwick said power lines were also dangerous because they could fall and come into contact with trees.

Meanwhile in the South Island, Fire and Emergency New Zealand said extreme fire risk in Nelson and Tasman was the worst in more than a decade.

The Tasman District Council has shut public access to its forests in Richmond and on the popular picnic and beach area at Rabbit Island.

Crowds were gathering on the Takaka Hill for the Luminate Summer Festival involving thousands of campers in the Canaan Downs, which is in the zone of high fire risk. A total fire ban was also in place there.

Fire and Emergency New Zealand rural regional manager Richard McNamara said the organisation was working with the festival organisers, the council and the Motueka police on an evacuation plan if it was needed.

A weather change was expected later in the week but more hot, dry winds were likely to precede it, he said.