Firefighters are investigating the cause of a ferocious fire that blazed through trees and scrub in Wānaka, sending flames leaping metres into the air and forced the evacuation of 22 homes.

The blaze broke out near Lagoon Avenue at 7.30pm on Saturday night and tore through steep hillsides close to houses, fanned by strong winds.

Fire and Emergency said no houses had caught fire on Saturday, although emergency services initially thought seven to eight properties were under threat.

Fire and Emergency (FENZ) crews brought the flames under control using eight trucks and three support vehicles, but were still dealing with hotspots, flare-ups and flying embers late into the night.

In McLellan Place, Marty Lohrey said he had been shocked to open the curtains to see flames tearing through kānuka behind his house.

"Very quickly they just flared up, within a few moments, probably 10-20 metres in the air. Quite quickly the wind just whipped them down the terrace. It was really hot, noisy, and all the embers were blowing across the houses. It made you think of the forest fires we've seen, everyone was pretty scared," he said.

Lohrey said neighbours were knocking on each other's doors and calling 111.

"I think we've dodged a bullet because there's no property damage. The fire boys were all here pretty quickly. The response by the fire brigade and police has been fantastic," he said.

Corey Young said he saw a bright glow in the sky from his living room and raced out to help the firefighters.

"They got on top of it pretty quickly but it was very, very close to a number of houses, it was pretty scary actually," he said.

"It was looking pretty grim there for a little bit until they arrived on the scene.

"I could feel the heat from the fire. Some of the flames got probably a good 20 metres high at times. It was just making sure that the people in those houses were safe."

Young said people were ready to use garden hoses and buckets of spa pool water to try to protect their properties.

"It was pretty touch and go there. There was smoke billowing everywhere," he said.

Hunt Place resident Del Tubb told RNZ the fire started with a roar: "[We] looked out the window and it was like a blazing inferno right across the garden. Everything was bright red and there were embers. It was pretty scary stuff," he said.

He quickly grabbed warm clothes to go out into the night and moved two cars. Talking on Saturday night he was relieved a woodshed just over the fence from the flames had not gone up in flames.

Strong winds and fire a bad mix, firefighter says

FENZ assistant district commander Nic McQuillan told RNZ that dry, windy weather was problematic, even in winter.

"We don't know how the fire started but I would just ask people to be conscious of the fact that even though it's still coming out of winter, everything is dry, the wind is a real problem when it comes to a spark or an ember that gets out of control," he said

McQuillan said people getting rid of ashes from fires should make sure they are completely cool before disposing of them and check if conditions are safe before lighting a fire.

MetService had issued a strong wind watch for Central Otago and Queenstown Lakes District for the period from 5am, to 1pm on Sunday.