The blaze started on Tuesday at around 2pm local time (1am UK time) near the small community of Wakefield, around 16 miles south of Nelson.
Fanned by near-30mph winds and extremely dry conditions, the fire was reported to have grown to almost 2,000 hectares by Wednesday.
The winds had “led to the fire creating its own extreme behaviour”, according to Tasman Council.
“Due to this, crews have not been able to access the forest areas and are instead focusing on controlling the fire when it is spotted onto grassland,” a spokesman for the authority added.
More than 60 firefighters, many of them volunteers, battled the blaze overnight, with several helicopters and planes involved in the operation.
Winds led to the fire ‘creating its own extreme behaviour’, officials say
The fire burned through the settlements of Pigeon Valley, Eve Valley and Redwood Valley, the latter where several homes have been lost, according to the Tasman Marlborough Fire Area.
About 150 homes have been evacuated and at least 70 households registered at a shelter for evacuees overnight.
Residents downwind of the fire have been warned to be ready to leave at short notice.
The area is mainly lifestyle blocks and farms, with a significant quantity of plantation forestry on the hills behind.
Thick smoke could be seen many miles away and there were reports of eye irritation and ash falling onto the streets as far away as Nelson.
Thick smoke could be seen many miles away
New Zealand’s national institute of water and atmospheric research said that the smoke could reach north of Wellington, New Zealand’s capital, which sits at the bottom of the North Island – more than 120 miles from the fire.
The Nelson-Tasman region has been extremely dry for many weeks, with a lack of rain leading to strict water restrictions being imposed earlier this week.
Some rain had been expected early on Wednesday but it turned out to be minimal.
Tasman mayor Richard Kempthorne told Radio New Zealand that emergency services were doing their best in difficult conditions.
He said: “It will be hours, if not a day or two, before the fire is completely out.”
He told TVNZ that the area was “massively tinder dry” and it had been an “awful spectacle to see [the fire] spread”.
