Cyclone Cook is just hours from landfall and is expected to carve a furious path the length of the North Island.
MetService has issued extensive gale and heavy rain warnings across a swathe of regions ahead of the storm coming ashore in the Bay of Plenty this evening.
It is expected to track south down the island reaching Wellington or Wairarapa in the early hours of Friday.
The forecaster is repeating warnings that Cook remains a "very significant event" likely to result in widespread flooding, slips and wind damage so bad roofs may be lifted and large trees toppled.
It says destructive gusts of more than 150km/h or more are possible affecting nearly everywhere between Auckland and Wellington.
On top a threat of coastal areas seeing colossal waves higher than 5 metres battering shorelines especially in eastern Coromandel Peninsula and Bay of Plenty. MetService warns these storm surges near the centre of the cyclone may cause flooding and erosion.
In addition, heavy rain is falling over parts of the country.
It's expected another 100mm of rain will fall in the flood-ravaged Bay of Plenty and Coromandel Peninsula, with lesser amounts in other areas, before Cyclone Cook moves away to the south tonight.
But it now appears the South Island may escape the worst with heavy rain warnings lifted for North Otago, Dunedin and Clutha.
MetService warned motorists to consider altering their Easter plans with driving conditions likely to be hazardous.
"People should be aware that this is a very significant event and is likely to produce widespread flooding, slips and wind damage, including to powerlines and may even lift roofs and bring down large trees," said the forecaster.