Eighteen people were evacuated in Ōhura, a small town in the central North Island.
The district council declared a State of Local Emergency at 3.21am today after 100mm of rain fell within 24 hours.
In Bay of Plenty, a tornado cut power to 75 homes in Tauranga's Welcome Bay, according to Powerco.
Ruapehu Civil Defence today urged travellers to respect road closure signage after multiple reports of people driving through floodwaters and closed roads, hindering response efforts and creating issues for themselves.
Civil Defence Controller Clive Manley said a number of incidents had occurred, including one traveller reaching Ōhura and running out of fuel.
“Over one hundred vehicles have been reported travelling through Ōhura despite road closures and unsafe conditions,” Manley said.
“Extensive slips mean that through roads are not open, and contrary to earlier reports, State Highway 43 (Forgotten World Highway) from Taumarunui is also currently closed.”
Travellers were warned not to attempt to bypass closures and to wait for official updates.
An Emergency Operations Centre has been activated at the Ruapehu District Council's main office in Taumarunui, where the council would coordinate the response and support affected people.
The Minister for Emergency Management and Recovery, Mark Mitchell, was expected to travel to Taumarunui today give a first-hand update on the weather.
Ruapehu Mayor Weston Kirton told RNZ the Minister allowed the council to use an Air Force helicopter or fixed-wing aircraft to help people stranded in Ōhura. Red Cross was also available to provide food and other resources, such as bedding.
Mitchell was expected to fly in by helicopter from the Air Force's largest base in Ohakea to Taumaranui, and then would head to Ōhura with Kirton.
Ōhura had been completely isolated, with residents and tourists stranded. Those evacuated went to the Ōhura Memorial Hall, in Ngarimu St, and were looked after by "some of the local people with a limited resource".
Later in the day, a small number of travellers were able to leave the town, with assistance from farmers.
Manley said farmers had also been playing an important role in supporting the response by helping to clear slips from lroads where possible. They were also checking on farm damage and stock losses.
The Red Cross was expected to begin welfare checks in Ōhura, now that access was available for emergency services. Staff would work with iwi already supporting the community.
Only a small number of requests for food parcels had been received, Manley said, and there may be a need to arrange overnight accommodation for travellers unable to leave the area.
Ōhura resident Mike Crowley returned home on Saturday afternoon, which was "a pretty rough trip home coming up from Whangamōmona on the Forgotten World Highway", but did not expect the inundation of water.
He said another resident, who had been living in the town for 35 years, warned him that it was going to flood about 11pm.
There had been similar floods in 1998 and 1956.
"A lot of the houses that were affected then, the ones that are still lived in, have been affected again. So there's some people that are going to be quite devastated."
Crowley believed they were unable to be insured due to the risk. Six people had chosen to evacuate, but Crowley had remained at home.
"I'm in the flood area, but I built my little whare, you know, a metre above ground, and 500 above the '98 flood. So yeah, I'm pretty safe."
Crowley had driven around the town and did a Facebook Live from Ngarimu St earlier on Saturday.
"It was completely covered at 3am this morning. [The water's] probably dropped three feet.
"It didn't go into the old BNZ house on the main street, but it was right up to the doorway. Whether it got in the Cosmopolitan Club, I'm not too sure yet... The old Ford dealership - that's got water flowing through it, that old building."
Crowley said it was "nothing the town hasn't dealt with before", but thought people would think twice about living in Ōhura in the future.
Whanganui on alert
An emergency mobile alert was sent to the people in Whanganui area, Civil Defence advised this morning.
Heavy rain in the upper reaches of the Whanganui River, combined with high tide, was forecast to bring possible flooding to Anzac Parade and Taupo Quay areas, and to the Putiki suburb about 1pm today.
People should prepare to evacuate immediately and Civil Defence staff were door knocking in these areas. If you feel unsafe, leave immediately.
Whanganui's mayor Andrew Tripe said this afternoon some people have left their homes as a precaution and so far there was only minor flooding.
"There might have been some minor breaches along the riverbanks but it's pretty good. We've got a little bit of flooding in some of our buildings that are pretty close to the river but I think we're going to be okay.
"We're anticipating that the large deluge of water will come down with the high tide about now so it's a wait and see. My anticipation is that we'll just make it in regard to getting off this relatively lightly."
Putiki Marae is nestled near the banks of the Whanganui River and trustee Tamahau Rowe said they were monitoring the rising floodwater.
"We're just down here having a look and if we need to evacuate, we will evacuate. There are some people who have made sure that they're ready to leave and we've got people who are on stand by keeping an eye on the river."
Rowe said residents were alerted to the potential danger of the river flooding by a text alert, Civil Defence door knocking and talking to people. "They've definitely given us ample warning that the river's rising up."
Highways affected
State Highway 3 between Mokau and Piopio in northern Taranaki will remain closed today following more heavy rain and slips overnight, the New Zealand Transport Agency advised.
The stretch of SH3 closed overnight pending a safety assessment this morning.
"Crews are continuing to assess SH3 with trucks and excavators currently working to clear lanes."
Within the first kilometre of the gorge, 25 truckloads of material had so far been removed from the road, with more to come, it said.
SH43, also known as the Forgotten World Highway, has closed again between Whangamōmona and Taumarunui, due to flooding.
