A severe storm is battering the top half of the North Island, with slips cutting off townships as heavy rain, gale winds and tidal surges combine.
On the Coromandel Peninsula, the main township of Thames was isolated after highways both north and south were shut.
Police urged residents to stay indoors as the bad weather has caused slips, toppled trees and knocked over a power pole.
State Highway 25 from Jellicoe Crescent to Maramarahi, south of Thames township, was closed about 9pm, while north of the town, the highway would be closed from Victoria Street North to Coromandel township, police said tonight.
The closures are because of the incoming tide, which reached high tide at 10pm.
"Slips and trees down have also worsened the problems,'' Inspector Kerry Thomas said.
"Thames township and residents further up the highway will not be able to leave or re-enter the area until the tide subsides and damage is repair or removed.''
A yacht had broken free from moorings in South Thames, but it was too dangerous to reach it, police said.
On the East Coast, three families in Tolaga Bay "self evacuated" over fears of being cut off by rising river levels.
The Uawa River breached its banks and washed over the main bridge, a central district police spokesman said.
The township was likely to be cut off at its southern State Highway 35 entrance because of the bridge being inaccessible.
Slips on the East Coast had caused rockfall along State Highway Two between Gisborne and Opotiki.
One driver's car had sprung two flat tyres as it went through the debris, the spokesman added.
The storm has already hit the Auckland region and northwards, where residents in some areas were told to prepare for flooding.
State Highway One, south of Warkworth, was closed due to a large slip.
Police saod the Pohuehue Viaduct was partially covered by the slip, and contractors were making their way to the scene.
The alternative route from Auckland to Warkworth is through Helensville, using State Highway 16.
But police warned that flooding, slips and trees were causing problems all over the region.
The deep subtropical low was expected to lie over Northland tonight, with rain and southeast gales spreading over most of the North Island and upper South Island.
Low-lying areas of Orewa, Omaha, Point Wells, Whangateau and Waiwera were all at risk of being inundated, Auckland Council spokesman Glyn Walters said.
Walters said the high-risk times would be a couple of hours either side of the 11pm high tide. Residents had been told that contractors were available for help with sandbagging, if needed.
A high wind warning for the Coromandel was extended to Eastern Waikato, and Waikato Civil Defence were on high alert as the weather threatened the leeward side of the Kaimai Ranges.
Residents were told to secure loose items and take care on the roads with gusts of up to 130 kmh threatening to uproot trees and cause havoc to power, telecommunications and larger vehicles on the roads.
Heavy rain of between 100 millimetres and 120mm was also expected on the Coromandel Peninsula before easing overnight.
In an early callout, the Waihi Volunteer fire brigade dealt to a pine tree that blocked one lane on the Waihi-Whangamata road.
Chief fire officer Moe Stevens said the brigade cleared the tree from the road before roading crews arrived to take over the scene.
"It looked a pretty healthy tree and yet it was basically rotten at the base. I’m just glad it happened this afternoon and not tonight," he said.
Metservice communications meteorologist John Law said the Eastern Waikato was most susceptible to strong winds particularly in the leeward side of the Kaimai Ranges and damage would be expected.
"These are strong winds and it's not out of the question to see some damage. It's not surprising at all."
The region would have to batten down the hatches overnight but with the low pressure system remaining close, he expected the wind to change change to a southwesterly direction.
Waikato region Civil Defence spokesman Stephen Ward said reports of gusts of 120 kmh around the Coromandel and they were keeping a close eye on the situation.
"There's the tidal issues and the rain as well so there’s quite a mixed bag of influences there."
He said civil defence workers on the ground expected the situation to "get a bit livelier" as the night wore on and they urged people to be safe and avoid unnecessary travel.
"Be aware of the risks and we’ll just have to do an assessment in the morning of what impact events have had overnight."
Auckland Transport said heavy rain had caused some flooding on the North Shore. All roads were open, but motorists were urged to take care.
A fire communications spokesman said crews had been called to about 15 incidents, mainly involving fallen trees and branches, since rush hour in Auckland, mostly in the Takapuna and Birkenhead areas.
He said there had been no major car crashes as a result of the weather.
Other areas including the eastern hills of Northland, the Hawke's Bay ranges and coastal hills south of Cape Kidnappers, and eastern Marlborough are expected to see heavy rain also.
MetService meteorologist Dan Corbett said the rain in Auckland would become heavy and the winds would pick up.
Earlier in the day Ports of Auckland said they were closing to shipping from 3pm today to 7am tomorrow if predicted strong winds materialised.
Auckland's Shed 10 would be open for business for those keen to brave wild weather for another America's Cup race on the big screen.
A Waterfront Auckland spokesman said the venue would remain open, despite the neighbouring port's temporary closure.
For the rest of the country, MetService said rain would become heavy overnight in eastern Marlborough, including the Kaikoura Coast and ranges, before easing tomorrow afternoon.
Up to 150mm could fall in the Gisborne ranges, with up to 100mm near the coast.
Winds could reach 120kmh in the central North Island high country, Taranaki, Horowhenua and the Kapiti Coast, and the Marlborough Sounds.
Rain could also be heavy in western Bay of Plenty, Hawke's Bay and Wairarapa, and in the hills and ranges of Canterbury north of about Waipara.
Corbett said the centre of the low would be moving across the North Island Central Plateau by tomorrow night and by that point would be starting to ease.
The wind would then turn into a southwest flow on the back side of the low.
"This is a good sign because by this point, later on Wednesday, the low is starting to ease and it's just flailing its arms around," he said.
There would still be some heavy rain through eastern parts of the South Island and in Northland, but it would be starting to ease.
"By the time we finish off Thursday we're finally kicking this low out the back door," he said.
- © Fairfax NZ News
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