Motorists are being urged to take care on State Highway 1 north of Kaitaia due to a breakout of the Kaimaumau fire.
As of 4.45pm today strong winds and high temperatures caused the fire to flare up near the highway about 2km north of Big Flat Rd, between Waiharara and Houhora.
Initial reports were that flames had jumped the road and vegetation was burning on both sides of the highway.
However, a reporter at the scene said flames were about 100m from the road.
Police were slowing down traffic but motorists were still allowed through.
There were currently no issues with visibility because the wind was blowing the smoke away from the highway. Helicopters with monsoon buckets were working to douse the flames.
Three helicopters had been working on the fire this afternoon but that has been boosted to six since the latest breakout.
The fire has been burning for almost three weeks and has covered 2400ha.