MetService has issued heavy rain and strong wind watches as a tropical cyclone heading for the upper North Island intensifies in the Coral Sea.
Tropical Cyclone Gabrielle is currently hitting New Caledonia. Aircalin flights from Auckland to Noumea, and Noumea to Auckland for tomorrow have been cancelled.
It is expected to make landfall in Northland on Sunday and has been upgraded to category 3.
It is also forecast to last until Tuesday, sweeping through Auckland, the Coromandel Peninsula, Hawke's Bay, Bay of Plenty, and Gisborne. It is possible that even Wellington could see some impacts, MetService said.
A heavy rain watch is in place for Northland, Auckland including Great Barrier Island, Coromandel Peninsula, and Gisborne from Sunday and until Tuesday. For Hawke's Bay, the heavy rain watch is a bit later, starting on Monday and ending Wednesday.
A strong watch is in place for Northland, Auckland north of Whangaparaoa as well as southwards, Great Barrier Island, and Coromandel Peninsula from Sunday until Tuesday.
Civil Defence authorities and mayors in the upper North Island are advising people to take precautions and stay up to date with the latest forecasts. More information on being prepared can be found here.
Minister for Emergency Management Kieran McAnulty said National Emergency Management Agency's (NEMA) National Coordination Centre was still in operration and ready to scale up to coordinate whatever assistance impacted regions need.
NEMA is facilitating all requests for national assistance from Auckland Emergency Management including military personnel.
Auckland and Thames-Coromandel yesterday extended their state of emergency due to the risks.
Coromandel Civil Defence said it was likely some low-lying coastal communities would need to be evacuated or be advised to self-evacuate before the cyclone hits the region, but a final decision was expected later on Friday.
Up to 300mm of rain is expected on the Coromandel Peninsula between Monday and Wednesday.
There would be four to seven metre waves, anywhere between north cape and east cape, and into Gisborne, MetService meteorologist Georgina Griffiths said.
It would be a major coastal event, she said.
"It's a significant wind event anywhere between Hawke's Bay and Northland, so prepare for one."
What's expected for Auckland
Auckland is already in the midst of a clean-up after heavy rain in late January caused flooding, slips, and damage to properties and roads.
The saturated ground along with the upcoming predicted rainfall and winds could cause large impacts, including flooding, land slips, tree falls and power outages, in the worst case scenario, Griffiths said.
"The rainfall totals for three days are rather large," Griffiths said. "200-300mm for [Great] Barrier and north Auckland, 100-200mm of rain over the event elsewhere. These are pretty significant rainfall numbers for Auckland, even if we weren't impact already."
It was hard at this stage to know which regions would see the most signficant rain rates, that would be clearer on Sunday, she said.
Heavy rain watches were likely to become warnings, and some may become red warnings, she said.
"Regardless of the track, wind will be a problem for Auckland."
As swells build on Sunday, sea conditions were predicted to be dangerous on Monday and Tuesday, she said. There was potential for sea surge too, if the cyclone does come close to Auckland's coast.
Residents have been told to be ready evacuate at short notice and ensure they have three days worth of food and water.
Auckland's roading network
Auckland Transport will be publishing a list of roads prone to flooding, and among them are Fred Thomas Drive, Takapuna, Wairau Valley Road, North Shore, Fanshawe Street, central Auckland and Tamaki Drive, east Auckland.
Harbourmaster has also issued an alert to vessels to check their safety.
The Harbour Bridge will be monitored for winds to make calls on speed restrictions or potential closures.
Preventative work is underway ahead of the storm to stabilise roading infrastructure.
Emergency services in Auckland
Auckland Emergency Management duty controller Rachel Kelleher said the difference between this weather event and what was seen last month is that it will come with really heavy winds.
"With that we can expect things like additional tree fall, so that could mean roads being blocked...bigger power outages than we saw last time but also things like coastal surges potentially around the eastern coastline."
Kelleher said they would have a limited supply of sandbags available at three stations in Westgate, St Heliers, and Mairangi Bay, which would be open from 8am to 8pm on Saturday and Sunday.
She asked that people only take what they need and heed advice on how to use them because they could become obstacles if not put properly.
The Sandbag Store was down to selling empties on Friday morning, but these had also nearly run out.
People are asked to hold off on putting any more flood-damaged property onto kerbsides and to them to one of the council's 15 drop-off spots before Sunday.
Fire and Emergency in Auckland has brought in additional resources to deal with any impacts.
They urged people to stay off the roads for non-essential travel, do not drive through flood waters, and only call 111 if someone's life is at risk - for example, if you are trapped and need to be rescued, if there is a fire or land slide.
Auckland Council building consents general manager Ian McCormick asked people to avoid red-stickered buildings. For yellow-stickered ones, follow directions and as a precaution stay away from them during this weather event, especially if there was ground movement associated with the previous flooding.
Properties around those stickered should be vigilant too.
The council is contacting the owners of properties, about 700 to 800, where it has detected ground movement to give safety advice.
Meanwhile, police are investigating reports of people impersonating Auckland Council officers to get into flood-damaged buildings.
Superintendent Grant Tetzlaff asked people to be vigilant and report any suspicious behaviour. He said officials wore uniforms and carried around identification, which they could be asked for.
There have been a number of arrests for burglaries at red and yellow-stickered properties, Tetzlaff said.
There will be ongoing reassurance police patrols.
Advice for boaties
Northland regional harbourmaster Jim Lyle is warning recreational vessels not to venture out to sea ahead of Cyclone Gabrielle.
Boats should shelter from Sunday to Wednesday instead, and seek secure berths if possible, Lyle said.
Boaties should not leave vessels unattended at anchor and should be prepared to run motors to stop their boats dragging.