New Zealand is preparing for Cyclone Vaianu with authorities bracing for a potentially “significant and damaging” storm, as the first North Island weather alerts are issued ahead of the Category 3 storm hitting.

MetService says the cyclone is expected to first move across the top of the country this weekend, with the entire North Island now under a strong wind watch for 22 hours from 1am to 11pm on Sunday.

Acting Minister for Emergency Management and Recovery Chris Penk told the Herald there’s potential for Cyclone Vaianu to be “significant and damaging”.

Fresh out of an emergency ministerial briefing this morning, he said the Government is not taking the storm lightly and neither should Kiwis.

“There’s certainly potential for Vaianu to be significant and damaging.

“It’s unwelcome news for the areas recently affected by bad weather ... just recently, at the start of the year and of course Cyclone Gabrielle and other floods.”

The entirety of the North Island is under a strong wind watch for Sunday 1am to 11pm, as Cyclone Vaianu makes its way down. Photo / Metservice

All eyes are on Northland and the upper North Island as the cyclone is expected to reach the top of the country by Saturday.

Penk told the Herald the potential scale of the storm is “beyond the recent experience coastal and rural communities have recently had”.

“We advise people take reasonable steps and precaution, as has the Government. We aren’t taking this lightly.

“If it isn’t as bad as we think that’s obviously good ... but it’s best to anticipate the worst in this situation.”

When asked if Metservice meteorologists describing the cyclone as “life-threatening winds” is accurate, Penk said he “wouldn’t second-guess the work of meteorologists”.

The latest track of Cyclone Vaianu has been projected by the Joint Typhoon Warning Centre. 

He said although it’s tracked for Northland to be first in line, there’s potential for the storm to reach anywhere in New Zealand including the South Island.

“It’s subject to other weather systems while it makes its way down so we’ll know closer to Sunday about areas in the south.

“It doesn’t look like it will be a particularly long-lived storm but it certainly seems to me the event will have potential severe impacts.”

MetService reported it was forecast to move southeast across the North Island towards East Cape by midnight Sunday, with the potential for severe gales in Tararua and Manawatū districts.

Giant swells of up to 8m have been forecast from 1am on Sunday, mainly in the east of the Far North, making their way down the east of the country and easing off around Gisborne by Monday afternoon.

Penk said Civil Defence, local help centres and NEMA have “prepared well” and the Defence Force has begun proactive planning.

The Far North District Council has set up recovery hubs to support locals affected by recent severe weather, as more rain looms for the area.

Bay of Plenty MP Tom Rutherford said the National Emergency Management Agency and civil defence emergency management groups were monitoring the situation.

In Whangārei, Mayor Ken Couper said the region is “hanging on by a thread” as the area was already recovering from two storms and recent rain.

“We’ve got to be saying to ourselves that the northeast region is hanging by a thread, isn’t it?

“They’re starting to feel the strain and are concerned about what’s coming.”

Category 3 storm brings 185km/h and 8m waves

As Vaianu edges closer, a Fiji Meteorological Service (FMS) spokesman in Nadi told the Herald the Category 3 storm has sustained winds of 130km/h at its core and 185km/h gusts, with waves towering more than 8m in some areas.

“The last available information showed waves in excess of 8m in the centre and rainfall at more than 50mm and in some places 100mm, in a 24-hour period.

“It’s wreaked quite a lot of havoc ... some of our weather systems are also not working properly because we’ve had power outages, so they need to restart.”

The FMS spokesman believed there’s “barely a possibility” the storm moves to Category 4.

Flash flood warnings remain in place for mainland Viti Levu and for all low-lying and flood-prone areas.

All schools across Fiji have closed under a Government-led directive and multiple flights to and from the island have been cancelled.

Fiji Meteorological Service said Vaianu has moved southeast at about 20km/h.

The handover to MetService will be “later this evening”, he said, when Cyclone Vaianu is expected to reach New Zealand waters.