Severe gusts reaching velocities of as high as 155km/h (96mph) have left around 90,000 homes experiencing outages and led authorities to cancel more than 100 flights, according to local media.
These gusts are influencing the complete southern region and lower areas of the North Island, as stated by the weather forecasting body.
The nation's agencies have announced infrequent severe gust advisories - the top caution category - in key areas including these major districts.
People have been urged to stay indoors, stay off roads, and make arrangements for further power and communication outages.
Broad Impact and Emergency Measures
The power cut appears to be affecting residences predominantly in the South Island, while authorities say that power was being gradually reinstated.
Local media have stated that in various locations homes have lost their roofs, and power lines and trees have been knocked down by the gales.
In Wellington, a person was fatally injured after being impacted by a falling limb at a well-known hiking path on earlier this week.
Also in the capital, a individual was swept into approaching vehicles on a road by a intensive burst, in a incident that was filmed in a viral dashcam video.
Flights entering and leaving the urban area have been halted due to the winds, whereas some roads and libraries are also closed.
At the same time authorities in Canterbury have declared a state of emergency, to assist disaster response efforts.
Strike Action Amid Severe Conditions
The powerful gales on Thursday occur while tens of thousands of teachers, doctors and other public workers are engaged in what has been termed a "major walkout", requesting improved salaries and workplace environments.
Yet the extreme weather has compelled them to change certain arrangements, with some outdoor rallies moved indoors or cancelled.
Similar gusts are also sweeping the nearby nation, causing a heatwave to the country's outback.
Authorities have declared burning restrictions for fear of wildfires.
