Intense gales reaching velocities of up to 155km/h (96mph) have resulted in around 90,000 households experiencing outages and led authorities to cancel more than 100 air travel services, according to local media.
The gales are affecting the entire South Island and southern parts of the North Island, according to the country's meteorological service.
Officials in New Zealand have announced rare red wind warnings - the highest alert level - in core zones such as Canterbury and Wellington.
People have been encouraged to avoid going outside, refrain from journeys, and make arrangements for additional utility disruptions.
Widespread Damage and Emergency Measures
The power cut appears to be affecting residences mainly in the South Island, while agencies say that the electricity supply was being restored progressively.
Local media have reported that in certain areas structures have suffered roof damage, and utility poles and vegetation have been knocked down by the winds.
Across Wellington, a person was fatally injured after being hit by a wooden fragment at a well-known hiking path on Tuesday.
Also in the capital, a female was blown onto approaching vehicles on a road by a strong gust of wind, in a event that was filmed in a viral dashcam video.
Flights in and out of the metropolis have been halted because of the gusts, and various routes and public facilities are not operating.
Meanwhile Canterbury officials have issued a state of emergency, to facilitate recovery activities.
Labor Protests Alongside Harsh Conditions
These intense gusts on this day coincide with tens of thousands of school staff, physicians and civil servants take part in what has been described as a "mega strike", calling for better pay and working conditions.
Yet the severe conditions has forced them to change various scheduled activities, with several external protests relocated inside or cancelled.
Similar gusts are affecting Australia, causing a high-temperature event to the remote areas.
Agencies have issued fire bans for fear of forest fires.
