Wind gusts of up to 160kms per hour have challenged crews battling the fire-ravaged Lake Ōhau Village in the Mackenzie Basin.

Around 40 houses have been destroyed or damaged following the wildfire, which started during the early hours of Sunday morning.

About 90 residents were evacuated after the fire broke out, with locals following a pre-determined plan, it said.

As of midday on Monday the fire had burnt 4600 hectares, of which 1900 hectares is conservation estate, Fire and Emergency said on Twitter.

Fire and Emergency region manager Mike Grant told Morning Report that conditions were tough for his crew overnight.

"We've had quite a few resources on the ground overnight as we did the night before, couple of areas certainly around the village where there's hotspotting trying to protect the unburned properties, but more importantly down at the southern boundary where they are actually on site at the moment experiencing a steady 80km/h wind but it's gusting up to 160km.

"It's certainly challenged and tested the fire lines that are put in at the south end, but good to say that they have been contained ... we're expecting a bit of a let up at around 10am this morning so we're hanging on and trying to resource that up until then and see what comes."

He said firefighters are focussing on two spots in particular that could breach the boundary perimeter.

"There's a lot of farmland [in that area] which some of it is tussock country, there's a lot of undeveloped land as well which more dry, and certainly on the farm land there's shelter belts and they've had shelter belts removed and [so] there's logging debris and so the fire's burning in some of that debris, it has been for two to three days.

"These debris piles are really difficult to get out and so they've (firefighters) have been working tirelessly on those and strengthening lines around them for last couple of days. The potential for an ember to pick up and throw it where it's not wanted is real at the moment."

Grant said helicopters aren't able to operate in those conditions, but ground crews remain on site.

He said at this stage there is a window of opportunity for residents to go and retrieve belongings between 10am and 2pm today, however, if the strong winds continue that may not happen.

"At the moment, with the winds they way they are it'll be most likely be too dangerous around the village as well, there's a lot of loose material, particularly corrugated iron, that will be flying all over the show in these winds, that'll be something that will be monitored and assessed as the conditions change.

"That later in the morning [10am] coincides with probably the best forecast that we've got where we might see a slight change in wind with a light southerly coming through, if that happens the wind will abate for a while but then it will pick up again later."

'Looks like a nuclear bomb went off' - resident

Janet Brown, who owns a property at Lake Ōhau village, said it was a terrifying night when the fire started.

"The winds were so strong and I know how bad the winds get at Ōhau, it can get very fierce, but it was particularly bad and I couldn't sleep, no-one could sleep it was that bad, and I heard the siren which I had never heard before so I knew something was not right. We had these two big sliding windows that looked out to the mountains and it was all ablaze, it was orange, the whole sky and it was very close."

Brown, who had visitors staying with her, knew they didn't have long to get out.

"We woke everybody up, fortunately we were ready to fly out the next day so we grabbed the bags, chucked them in the boot of the car and got out of there as quickly as possible.

"There were lots of people in the village because of the school holidays, lots of cars on the road, it was incredible what the residents did to get everybody out, they knew this was going to happen and I can tell you this because of the wilding pine problem and it has to be sorted out, this is going to happen again and again and unfortunately I think people may die in the future if we don't do something about it now... I can not believe nobody died, it's a miracle.

"Well done to all those lovely people in the village that live there who were so organised to get everyone out, they are heroes, I'm very proud of them."

Brown said her family has lost everything in the fire.

"It's our only home, we don't own a home, this is it, we built it with our own hands, we lived in caravans with our children, we spent three years building it, our hearts and souls went into it, kids call it home, it's all gone.

"We don't have another home, but we're lucky we live in Auckland so we've got jobs and a place to live."

She said the community had been concerned about the wilding pine in the area for a long time.

"The people have been going out on their own and snipping the wilding pine for years and years and years with no help, it's all been voluntary.

"It was a disaster we knew would happen one day, I just didn't think it was going to be so devastating to us, I thought we'd be lucky and I was wrong."

As of Monday, Brown had only seen images of the damage, but described it as harrowing.

"It looks like a nuclear bomb has gone off."

Residents were given their first glimpse of the damage on Monday, as three buses took them on a tour of the area.

Graeme Still said it was a humbling experience to take residents to see the fire-affected area.

Still has been a firefighter for 40 years and said the damage to the buildings is the worst he has seen.

Fire and Emergency say crews have been working through the night to protect any further structures from being destroyed in the fire.

A drone equipped with an infrared camera was used to seek out hotspots.

Fire services said controlled access will be available between 10am and 2pm, if conditions are safe.

The access is only available for essential purposes, such as collecting medication, or tradespeople needing their tools.

Crews are working to reduce the hazards around undamaged properties, including fire-damaged trees, loose iron and debris, Fire and Emergency said.

It said that work will need to be completed before residents can be given unrestricted access.