Forecasters are predicting "widespread impacts" as Cyclone Fili tracks towards New Zealand - with heavy rain and wind warnings issued for many North Island centres, including Auckland.
MetService has this morning updated its forecast with both Gisborne and Wairoa now under a red heavy rain warning.
Great Barrier Island, Hawke's Bay, Coromandel Peninsula, Bay of Plenty, Rotorua and Northland east of about Kaikohe all remain under an orange heavy rain warning.
Gisborne can expect between 200 and 300mm of rain from 10pm tonight until 10pm tomorrow with up to 35 to 50mm/h of rain likely in some parts of the region on Wednesday afternoon.
While Wairoa will get even more soaked with 250 to 350mm of rain likely to fall from 1am on Wednesday until 4am on Thursday. It will be the hardest hit late Wednesday afternoon and evening with between 35 and 50mm/h of rain possible.
The rain is expected to cause dangerous river conditions and significant flooding. Slips and floodwaters could cause havoc to the roads and possibly isolate some communities.
There are also orange wind warnings in place for Auckland, Great Barrier Island, Coromandel Peninsula, Bay of Plenty, Rotorua, Gisborne, Hawke's Bay and southeast Taupo including higher parts of the Desert Road.
Wind gusts could reach up to 120km/h in most of those areas and damaging gusts of 130 to 140 km/h are likely east of Whakatane during Wednesday afternoon and evening.
Civil Defence Coromandel controller Garry Towler said Fili was fast approaching and the biggest concern for the area was the wind causing coastal damage, slips, power cuts and bringing trees down.
A lot of people had already arrived at the holiday hot spot or would be coming to the area for the next few days as Easter and the school holidays approached.
"As it's an overnight event, it will really kick in this evening and start to clear tomorrow morning," Towler told RNZ today.
All authorities could do for now was to warn people to take responsibility and prepare.
"Just avoid travelling," he said.
"From dark tonight stay off the roads - they are dangerous."
Towler said there was a high probability they would have power issues and that the wind would bring down trees tonight.
MetService were also instructing people to tie down or bring inside anything that wind could break or uplift. Trampolines should be turned upside down to minimise the surface area exposed to the wind they said.
Niwa meteorologist Chris Brandolino said Fili had shifted slightly to the east, but not enough to spare New Zealand from the impact.
Rain was already falling on the upper North Island, which would now be saved from the worst of the severe weather event, but it was still likely to do some serious damage to the already storm-damaged Tairāwhiti region.
Gisborne and Hawke's Bay would probably cop the worst of Fili with wind, rain and higher waves expected.
North of Napier to Gisborne could cop 200 to 300mm of rain by late Wednesday to midnight Thursday.
"That amount of rain in a short period of time - it won't take long for those soils to get saturated so you really have to worry about slips and flooding in that region," Brandolino told RNZ.
There could also be some "really incredible" wind gusts in Hawke's Bay and Gisborne regions from late tomorrow morning. Winds could gust well over 110km/h to 120km/h.
"You combine that with the wet ground. Things like trees coming down, power cuts, slips - it all becomes a distinct possibility if not a reality unfortunately."
'Widespread impacts to the North Island'
MetService said this morning that Cyclone Fili had shifted slightly east with a "narrower cone of uncertainty".
"Cyclone Fili is approaching the North Island from the subtopics on Tuesday, tracking southeastwards close to, or across, eastern parts of the North Island during Tuesday and Wednesday."
MetService warned widespread impacts to the North Island with heavy rain, severe gales and very large waves likely to affect northeast and eastern coasts.
The MetService said this would be a "significant weather event", as forecasters continued to monitor the cyclone's likely path.
Civil Defence teams across the North Island are preparing for what Cyclone Fili may bring today.
The cyclone that formed near New Caledonia six days ago is approaching New Zealand.
Recent monitoring from WeatherWatch found the cyclone's path moved further east, meaning severe weather risks may be reduced in some western areas.
Early this morning, WeatherWatch said the latest models show Fili could track even further east of New Zealand - potentially missing a direct landfall near East Cape.
If so, that will reduce severe risks in some parts of the North Island, it said.
"It's been a very challenging build-up to Fili with the storm falling apart last Friday only to re-emerge now as an extra-tropical cyclone again bringing severe weather risks.
"The low is now rapidly deepening as it approaches the upper North Island and will move in quickly tonight/overnight and Wednesday – before entirely clearing the North Island by Thursday morning."
Heavy rain warnings
Heavy rain warnings are in place for Northland, Auckland, the Coromandel Peninsula, Bay of Plenty, Rotorua, Gisborne and Hawke's Bay. The warnings for Fiordland and Westland were downgraded this morning.
Just two weeks ago the Tairāwhiti Gisborne region was battered with heavy rain and flooding and tomorrow's weather could see up to 300mm of rainfall in the area over a 27-hour period from 6pm.
MetService said heavy rain could cause streams flooding and slips, and rivers to rise rapidly.
Strong wind warnings have been issued for Gisborne, Auckland, Great Barrier Island and the Coromandel Peninsula.
Easterly gales could be severe at times over Gisborne from 9pm to 9am on Wednesday, with gusts forecast to reach 120km/h.
Auckland and Coromandel could be battling 120km/h southeast gales and 130km/h southwest gales while gusts could reach 140km/h out around Great Barrier Island.
Hawke's Bay residents to prepare
Hawke's Bay Civil Defence Emergency Management (CDEM) is warning communities to prepare for the severe weather the cyclone may bring to the region.
Currently there is a Heavy Rain Warning and Strong Wind Watch in place for Hawke's Bay, through to 9pm on Wednesday.
Hawke's Bay Civil Defence Emergency Management Group has activated a Group Emergency Co-ordination Centre to deal with possible ramifications of a cyclone zeroing-in on Northern Hawke's Bay.
It was already preparing infrastructure and staff for possible impacts.
"Hawke's Bay residents need to be prepared for heavy rain, strong winds and large waves," group controller Ian Macdonald said.
"Unfortunately, the brunt of the rain looks likely to once again impact the Wairoa District and Tairāwhiti where up to 300mm may accumulate in 24 hours, starting from late Tuesday or early Wednesday."
Residents may experience power outages, road and transportation damage, and coastal inundation from swells in some areas.
"We're urging people in the region, particularly in our rural communities, to be prepared and to have a plan in place to respond to heavy rain and wind.
"Ensure you have enough food, fuel and supplies for at least three days and please reach out to your neighbours and those who were impacted during the last rain event to ensure they are prepared as well."
Counties Energy crews on standby
Meanwhile, Counties Energy has storm response teams on standby south of Auckland.
Counties Energy GM operations Dale Carline said the company was preparing for a large-scale event and urged residents to do the same.
"Please start your storm preparations now to lessen the impact on the electricity network and on your loved ones.
"Take some simple steps now such as securing outdoor furniture and trampolines, and anything else that can become a projectile in high winds. Store some water if you rely on a pump, check your barbecue gas bottle and torches and charge up your smartphones and tablets."
Carline said residents should treat all lines as live, stay well clear and report any downed or damaged lines or electrical equipment immediately on 0800 100 202 or via 111.
In the event of large-scale power outages Counties Energy crew will move around the region isolating power to any damaged or downed lines and electrical equipment before moving to restore the network.
How to prepare – what to do
• Keep up to date with MetService weather forecasts.
• Work out what supplies you might need and make a plan.
• Be prepared to evacuate and keep your emergency grab bag near, particularly if you live close to waterways and steep slopes.
• Farmers and lifestyle block owners need to consider how and where you will relocate stock in a flood situation. Move stock and equipment out of low-lying areas.
• Storm events can damage water infrastructure so consider storing clean water for drinking, particularly if your home is in a flood-prone area or if you're on a non-reticulated supply or private supply.
• Act quickly if you see rising water. If you feel you, your family and/or your property are at risk, leave immediately and contact emergency services on 111.
• Do not attempt to drive or walk through floodwaters. There can be unknown hazards, like open drain holes and debris, and unseen hazards such as septic tank and sewage pollution.