Fires lit in early December to burn forestry slash have flared up again in the Waiouru-Ohakune area, spurred by easterly winds and hot dry conditions.
Firefighters spent the weekend battling two vegetation fires near State Highway 49 and Tangiwai.
Both originated from the burning of slash (forestry prunings), senior Ohakune volunteer firefighter Marty Webb said.
"With the weather and wind that we have had, and the heat, those fires have never gone out."
The fires would have been sheltered from the predominant northwest wind, but a breeze from the east on Saturday made them flare up. Both were fought by Waiouru fire crews.
Webb was hoping predicted showers predicted for this week would damp down the fire danger.
It's at high in the Ruapehu region, Fire and Emergency NZ group manager Renee Potae said. She expects the open fire season to move to restricted soon.
"We have had a lot of rain before Christmas, which created a good grass growth. Hot dry windy weather dries that out really quickly. Dry grass is fine fuel."
She asked people who are considering lighting outdoor fires to go to the checkitsalright.nz website first. Fire restrictions are regularly updated there, and the site gives tips and advice for safe fire lighting.