Cyclone Gabrielle raced into the country's north, causing catastrophic flooding and leaving tens of thousands of people without power, prompting New Zealand for the third time in its history to declare a national emergency.
Local media depicted individuals stranded on their roofs due to the increasing waters, houses destroyed by landslides, and roadways swamped in water.
In several regions, mobile phone service was also interrupted.
"It has been a significant night for New Zealanders throughout the country, but especially in the upper North Island... a lot of families displaced, a lot of homes without electricity, considerable damage was done around the country," Prime Minister Chris Hipkins told reporters on Tuesday after the emergency was declared.
The cyclone is now around 100 kilometres (60 miles) east of Auckland, near the east coast of the North Island, and is predicted to track nearly parallel to the shoreline as it moves east-southeast.
Kieran McAnulty, minister of emergency management, signed the statement as emergency services struggled to cope. The decision enables more significant resources to be allocated to the six hardest-hit regions.
"This is a once-in-a-lifetime weather event that is having significant effects on most of the North Island," he added. We face widespread flooding, landslides, and infrastructural and road damage.
As the cyclone progresses, it's anticipated that the severe weather may spread to the upper South Island as well.
McAnulty stated that the overnight weather reports were "extremely concerning."
Hipkins stated that it was too soon to determine how many individuals were displaced or hurt. There have been no verified deaths.
The national fire and emergency service reported that one firefighter was missing after a house fell in West Auckland. At the same time, another had been rescued and was in critical condition in a hospital.
A New Zealand navy ship is en route to a boat off the east coast that activated its emergency signal this morning.
Auckland, the largest city in New Zealand, is home to approximately 1,600,000 individuals. It was already a struggle to clean up after the region was devastated by heavy flooding two weeks prior.
Previous national emergencies proclaimed by New Zealand include the 2011 Christchurch earthquake and the 2020 COVID-19 pandemic.