Police have fears a bridge near Katikati could break with rivers in the Bay of Plenty starting to swell, as a storm system bringing gales and rain is hammering much of the country.
Have you been affected by the wild weather? Send your newstips, photos and video to email@example.com
The bridge is on Wharawhara Rd, which joins State Highway 2 south of Katikati and is now closed, Sunlive reported.
"We are concerned the bridge may break," Western BOP road police acting manager Sergeant Nigel Ramsden said.
"We are also very concerned about the second high tide at 9pm tonight, and there may be further road closures."
Waikato police were also advising against all but essential travel to or around the Coromandel, following the first heavy rains in several months.
Senior Sergeant Pete Van De Wetering said as at 12.45pm a number of popular holiday routes were closed due to a number of slips, fallen trees and flooding.
The road to Tairua and Pauanui, SH25A the Kopu-Hikuai Rd was flooded while SH25, the route between Whangamata and Tairua was also closed.
SH25 between Thames and Coromandel was flooded at Mania while SH25 between Whitianga and Tairua was also closed.
SH25 between Waihi and Whangamata was still open, but extreme caution was advised.
Another major route, SH2 between Paeroa and Waihi at the Karangahake Gorge, was expected to be closed by 3pm due to flooding.
WEST COAST WALLOPED
In the South Island, the extreme conditions were pushing emergency services to the limit on the West Coast.
Vehicles have blown over, many roofs have lifted off properties and windows have been blown in, plus trees and power lines have been downed.
Westport fire chief Pat O'Dea said at least three properties had lost their roofs this morning in the district.
At the worst-hit property on Wilsons Lead Rd at Cape Foulwind, the farmhouse's roof had blown off into a nearby paddock.
He said high wind made conditions too dangerous for fire officers to fix tarpaulins over the roof.
Instead, they were placing tarps over some of their belongings for temporary protection.
''And the wind is getting stronger if anything,'' O'Dea said.
All its resources, including 18 volunteer fire officers, had been called on to handle wind-related callouts.
West Coast area commander Inspector John Canning said Cobden, near Greymouth, was being badly buffeted by the strong winds, sending debris flying around to coastal township.
The road into Cobden had been closed because of the dangerous conditions.
Power lines had been downed just north of Whataroa, in Westland, also closing State Highway 6, he said.
He believed a large vehicle, possibly a truck, had been blown over near Whataroa and a bus had overturned near Reefton.
In Manawatu, emergency services are bracing themselves for what could be an afternoon of weather-related damage in the region.
Gusts of up to 140kmh and heavy rain are forecast throughout the day and rivers around the region were beginning to rise.
Power is out in parts of Apiti, Pohangina, Ashhurst and Aokautere due to faults.
The worst of the wind in the region is in Horowhenua where firefighters had to re-secure an air-conditioning unit to a building on Oxford St at 11.40pm, a fire communications spokesman said.
There were also reports of a trampoline blown onto the Main Trunk Line from Plimmer Tce in Shannon.
Firefighters were preparing for more callouts as the worst of the weather moved south, he said.
In Taranaki, flights have been cancelled and reports of damage were coming in as strong winds and rain took hold.
Cars on north Auckland's Whangaparaoa Rd had a close call when the roof landed on the busy four-lane arterial route at about 9.30am.
No-one on the road was injured and no vehicles were hit to the surprise of motorists and emergency services.
However, two elderly people in the home where the roof blew off suffered minor injuries and were taken to hospital.
To the north of the city, gales have been causing havoc across Rodney and the Hibiscus Coast.
Some residents say it was far worse than Cyclone Lusi on March 15.
Power cuts had affected thousands of homes across the district, including Orewa, Silverdale, Stanmore Bay, Snells Beach, Hatfields Beach, Helensville, Coatesville, Kumeu, Kaipara Flats and Tapora, Lines company Vector said.
Power was also out in Henderson, Massey, Howick, Remuera, Piha, and Whangaparaoa.
TAMAKI DRIVE UNDER WATER
Severe flooding on Auckland's waterfront, described as the worst ever seen, trapped residents this morning.
Waves crashed over the sea wall on Tamaki Dr as the high tide arrived at 8.42am.
"The waves are coming over the wall pretty heavily. We can't leave the house, so we are going to try and work from but the power keeps cutting out," said Jessica Desmond, who lives on the third floor of an apartment on the waterfront road.
"Tamaki Dr is a disaster," Kohimarama resident Zoe Gibbs, 83, who lives one house back from the waterfront, said.
"People who have lived here a long time called me and said they've never seen it so bad".
"It's all around my letterbox, across my lawn and halfway up my drive," she said.
There were delays at Auckland Airport as the storm disrupted flights.
High winds and rising seas were causing delays and cancellations for Interislander ferry trips across the Cook Strait.
There would be significant delays and slow crossings throughout the day on all ferries, KiwiRail spokeswoman Helen Corrigan said.
Sailings would likely be cancelled and customers should monitor the Interislander timetable, she said.
Bluebridge communications manager Wendy Pannett said the Straitsman earlier had difficulty berthing because of high winds.
The Santa Regina was also running a couple of hours late. Bluebridge was not anticipating any cancellations.
Alex Chong of Porirua was on the Straitsman's 3.30am sailing from Wellington to Picton.
He said when the ferry reached Picton, it was unable to berth.
"All the boat did was go round and rounds the islands from 6.30am until 12 o'clock," he said.
"Three truckies on board said it was the worst sailing they've ever been on, and truckies are on it almost every day."
Bluebridge staff checked on passengers and handed out cups of ice for passengers to put under their tongues to help with seasickness, he said.
Subscribe to a digital replica of The Southland Times.
Southland Times subscriber news and information.
Click here for information about advertising with The Southland Times.