Severe gusts reaching speeds of approximately 155km/h (96mph) have caused around 90,000 properties without power and forced agencies to cancel more than 100 flights, based on domestic outlets.
The gales are influencing the whole southern region and lower areas of the northern region, according to the national weather agency.
Officials in New Zealand have released infrequent severe gust advisories - the top caution category - in central regions encompassing Wellington and Canterbury.
Residents have been advised to stay indoors, avoid travel, and get ready for more power and communication outages.
Broad Impact and Crisis Measures
The electricity loss appears to be affecting homes mainly in the South Island, although authorities report that energy was being slowly brought back.
Regional news have indicated that in various locations homes have lost their roofs, whereas power lines and trees have been toppled by the gales.
In Wellington, a man was fatally injured after being struck by a falling limb at a frequent walking route on earlier this week.
Additionally in the city, a individual was swept into approaching vehicles on a road by a strong gust of wind, in a moment that was captured in a widely shared car camera footage.
Air travel to and from the city have been halted due to the gusts, while various routes and public facilities are not operating.
Meanwhile local leaders have issued a crisis declaration, to support disaster response efforts.
Labor Protests During Extreme Conditions
The wild winds on today come as tens of thousands of school staff, physicians and civil servants are engaged in what has been called a "significant labor action", calling for better pay and working conditions.
But the extreme weather has pressured them to modify various scheduled activities, with some outdoor rallies moved indoors or abandoned.
Similar gusts are also sweeping the neighboring country, ushering in a heatwave to the remote areas.
Authorities have issued flame prohibitions for apprehension regarding wildfires.
