Huge burning glow in the sky at uncontrolled fire near Aoraki/Mt Cook

Firefighters are still battling to slow a huge scrub fire burning since Sunday in Mackenzie Country, but bad weather overnight has helped their efforts.

Snow and heavy rain hit the area overnight, bringing more moisture to dampen the flammable materials in the fire's path, and helping those on the frontline trying to control the blaze.

By late Monday the fire near Lake Pukaki had burnt through around 3500 hectares of mostly wilding pines, and through the night it continued to create a red glow seen for many kilometres.

Mackenzie Emergency Operations Centre spokesperson Chris Clarke said an expected drop in high winds, plummeting temperatures, and forecast rain and snow that was expected to set in on Monday night should help throw the balance back towards the firefighters.

"Those high winds have certainly dropped a wee bit [through Monday evening] the forecast ... there may be some rain, even a little bit of snow, which is not good news to most people, but great news to people fighting a fire."

Clarke told Morning Report that while it was still too early to say the fire was contained: "Everything is in place to keep the fire contained.

"The intelligence we have is that the fire is contained within its perimeter."

No helicopters would be flying today due to "the snow-laden cloudy skies' but the wind dropping away to nothing was a significant help.

Ground crews will continue to carry out their work protecting any properties and keeping the fire within its perimeter, Clarke said.

The wind yesterday was blowing the fire away from the eight properties within the fire zone so they were no longer considered to be under any threat.

Bulldozers have created a fire break.

He was hopeful SH8 would reopen today, at least for Mt Cook residents but possibly the general public.

There was blackened earth all around NZ Alpine Lavender but the well-known property has been saved, he said.

The Pukaki Scientific Reserve has been extensively damaged by the flames.

According to a report from Landcare Research, the shrub land at Pukaki Scientific Reserve is the only home of a nationally endangered moth.

However, Fire and Emergency says despite the damage to the reserve, good progress was made on Monday in efforts to control the fire and defend property and structures in its path.

One hundred and fifty firefighters were working at the scene on Monday, with equipment including 18 helicopters, two planes and five diggers. Another 25 support people were also based in Twizel.

Wilding pines blamed

Environmentalists believe the prevalence of wilding conifer trees - better known as wilding pines - in the Mackenzie District should take much of the blame for the large scrubfire still burning there.

They say the spread of the invasive species has created tinder box conditions around parts of New Zealand particularly along the East Coast.

The government has injected $100 million to tackle the escalation of wilding pines for another reason, because of the threat they pose to native trees and wildlife.

Robin Piper from the Central Otago Wilding Conifer Control Group told Morning Report there is significant wilding spread in the Mackenzie region where they are spreading at the rate of 5 percent a year.

All up, wilding pines cover around 1.8 million hectares of the country, she said. The way to control them was to cut them down or use helicopters dropping herbicide in more inaccessible areas.

While the threat to native trees and wildlife was often cited as the main reason to control wilding pines, the growing fire risk added another impetus.

"We've seen quite a few big fires through pine forests, wilding or otherwise, in New Zealand and overseas. That focus is really brought to the fore and it can add a lot of urgency to it especially as these areas like the Mackenzie we've got towns like Twizel and Glentanner close to the wilding spread."