Three people are dead and seven injured after a tornado ripped through the Auckland suburb of Hobsonville, with police ordering people to shelter in their homes amid fears of a new twister.
The tornado, which hit about 12.15pm, ripped roofs from houses, toppled trees, and sent debris flying on to cars.
Hobsonville Point residents have been ordered to take shelter in their homes and cars.
On Carnegie Cr, residents were shut in their cars and houses just before 1.30pm.
The street was scattered with debris.
The ambulance service reported two deaths from the storm occurred at a construction site in West Auckland.
There are also reports of people being injured. A construction worker on a new high school site at Hobsonville told Radio New Zealand there were people missing, and many people injured.
"Pretty bad," a man called Sam said.
"We did a head count, I think there are a couple of people missing."
An ambulance spokeswoman said five crews were attending to different scenes.
"We are currently assessing seven patients all in and around Hobsonville."
The spokeswoman declined to comment in the patients' conditions.
Brendan Muir, who is working at Hobsonville Point, said he was sitting in a ute when the tornado hit.
"It was just mayhem. I had to put my seat belt on, I thought it was going to flip."
Muir said around him he could see trees "that looked like a plane had crashed into them", walls and fences knocked down and Portaloos scattered about.
He said for about 10 minutes there were so many sirens sounding it "seemed like 9/11".
Despite threats of another tornado on the way, Muir said he was back pouring concrete.
The storm has destroyed houses in the air force's married quarters in Clark Rd, Hobsonville.
A witness said the roof had been ripped form at least one house, and a tree had smashed through the kitchen of a house nearby.
Trees gave been uprooted, a trampoline flipped and fences crushed by the force.
Frances Schuster said the tornado only lasted 12 seconds but was terrifying.
"It went blurry for a while, it just happened so fast. It was really loud and the windows were shaking."
Part of a roof fell on to her car.
Tracey Standring, human resources manager at Hawkins Construction, said staff from the company were working on the Hobsonville Point School construction site when a tornado came through the site.
She was unable to provide more information about any damage.
There has been an unconfirmed report that a woman lost her house in the tornado.
The Defence Force base at Whenuapai in West Auckland has been hit by the storm.
Against the sound of sirens, the base operations said "we are very busy, cannot talk."
Auckland Mayor Len Brown says he was very concerned at casualties on Hobsonville Point.
"Also reports of surface flooding and damage in other parts of Auckland. Please stay safe and if possible stay inside until the weather clears," he said on his Facebook page.
CONDITIONS 'RIGHT' FOR TORNADO
MetService spokesman Daniel Corbett said the organisation had not confirmed there had been a tornado but conditions were right for small tornados to develop.
"Looking at the radar, we're seeing a line of thunder storms," he said.
Around 1pm the middle of a front was just moving onto central parts of Auckland. Converging winds at the front were favourable.
"It's certainly possible and over the next couple of hours converging winds within the front could allow the potential for these small things to happen," Corbett said.
There was also a risk of heavy downpours, strong winds, and hail.
There are reports of surface flooding across Auckland as a predicted thunderstorm batters the area.
The heavy weather was caused by a band of bad weather that was moving in from the west.
Corbett said the weather system was moving across the Waitakere Ranges and the Manukau Harbour and would hit central Auckland until 2pm.
The front was expected to bring up to 15mm of rain as well as thunder and lightning.
Earlier MetService said a cluster of active thunderstorms had approached southwest Northland this morning, and were forecast to move on to western parts of Auckland and Waikato.
The top half of the North Island had a moderate risk of thunderstorms until early afternoon.
Thunderstorms were possible in north Taranaki and Manawatu later today, while the rest of the North Island had a low risk of thunderstorms into the afternoon.
The storm risk was a result of a very warm and moist airmass moving southeastwards across the North Island, MetService said.
More heavy rain was also expected today in the ranges of eastern Bay of Plenty, with MetService warning streams and rivers in the area could rise quickly.
Between 60mm and 80mm or rain was forecast between 8am and 9pm, with slips and surface flooding also possible.
While heavy rain warnings had been lifted for Tongariro National Park and the Kaimanawa Mountains, a further brief burst of heavy rain was possible in those areas this afternoon, MetService said.
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