Almost a quarter of a million people were plunged into darkness yesterday and communities were cut off as Gabrielle wrought devastation, forcing thousands of evacuations from some of the hardest-hit regions.
About 42,000 Auckland homes remained without power.
Telecommunications, including phone lines and internet services, have been stretched, as police launched a major operation to cope with reports people could not be reached in some regions.
A national state of emergency was declared yesterday morning, with Prime Minister Chris Hipkins calling Gabrielle the most severe storm this century, leaving damage unseen since Cyclone Bola in 1988.
The New Zealand Defence Force yesterday helped rescue people from roofs of houses and cars inundated by flooding, and homes were destroyed by trees downed by severe gales.
Emergency Response Minister Kieran McAnulty said at least 2500 New Zealanders had been displaced.
In Tairāwhiti Gisborne, landline and cellphone services have been cut.
A fibre cable supplying internet services to the region was severed and the peninsula remained without electricity, while generators have been given to coastal communities.
On Auckland’s west coast, people were told to stay away from the devastated settlement of Muriwai, where a volunteer firefighter was missing after a slip fell on a flooded house being assessed late on Monday night.
At least 270mm of rain fell on the settlement.
Residents of regions most affected by Gabrielle’s destruction have been asked to conserve water, petrol and food, as response services were running out, after supply lines and infrastructure in Gisborne were stretched and severed.
Some 80 roads in Auckland alone were closed.
Coromandel was also hard-hit with more than 400mm of rain and gales "closing" the peninsula, already sodden by downpours in the past month, Civil Defence controller Garry Trowler said.
In Taranaki, tens of thousands of people spent Monday night without electricity and Taranaki Base Hospital reduced services to focus on essential visits only.
Gabrielle is expected to move away from the country early this morning but the effects will be felt for much longer with more rain forecast this week before fine weather this weekend.
Prime Minister Chris Hipkins said the country was "still in for a bumpy time ahead" and it was possible there could be more people displaced in areas with limited communication such as Gisborne.
He expressed "enormous gratitude" to the first responders and acknowledged those affected.
By Raphael Franks