Severe winds attaining speeds of as high as 155km/h (96mph) have resulted in approximately 90,000 properties without power and compelled agencies to halt over 100 air travel services, as reported by local media.
The gales are impacting the whole South Island and southern sections of the North Island, according to the country's meteorological service.
The nation's agencies have issued rare high-level wind alerts - the highest alert level - in key areas encompassing Canterbury and Wellington.
Locals have been advised to avoid going outside, avoid travel, and get ready for additional utility disruptions.
Extensive Impact and Crisis Measures
The power cut appears to be affecting residences predominantly in the southern region, while authorities report that the electricity supply was being gradually reinstated.
Local media have indicated that in some places structures have suffered roof damage, while trees and electricity poles have been brought down by the gales.
In Wellington, a man was killed after being struck by a wooden fragment at a popular trail walking spot on Tuesday.
Additionally in the city, a female was swept into oncoming traffic on a road by a powerful blast, in a moment that was captured in a widely shared car camera footage.
Air travel entering and leaving the city have been halted because of the gusts, while various routes and public facilities are also closed.
Simultaneously Canterbury officials have announced a crisis declaration, to support emergency management operations.
Work Stoppages Amid Extreme Conditions
The powerful gales on Thursday come as tens of thousands of teachers, doctors and other public workers take part in what has been described as a "significant labor action", requesting improved salaries and workplace environments.
Yet the extreme weather has pressured them to modify various scheduled activities, with some outdoor rallies moved indoors or cancelled.
Like conditions are also sweeping the nearby nation, causing a period of extreme heat to the nation's interior regions.
Authorities have announced fire bans for fear of wildfires.
