New Zealand Defence Force staff are cancelling Easter leave to help with the aftermath of Cyclone Cook.

Chief of Defence Lieutenant General Tim Keating this morning thanked personnel for cancelling their leave to "help New Zealanders affected by the storm".

The storm was expected to make landfall over the Bay of Plenty this evening and move south, reaching Wellington or Wairarapa early tomorrow morning.

The MetService said damaging severe gales with gusts of 150km/h or more were possible, affecting Auckland to Coromandel Peninsula and Bay of Plenty, down to Wellington. Coastal areas of eastern Coromandel Peninsula and Bay of Plenty may see large waves of 5m or more, storm surges near the centre of Cyclone Cook, coastal inundation and erosion.

Advertisement

More than 100mm of rain could fall in Bay of Plenty and Coromandel Peninsula, with lesser amounts in other areas, before Cyclone Cook moves south this evening.

Defence Force staff were called to Edgecumbe last week to help clean up after heavy rainfall from the remnants of Cyclone Debbie caused the Rangitaiki River stopbank to breach.

They were also called to help last month when about 200 festival-goers had to be rescued after torrential rain and a swollen river flooded the Sundaise Festival near Waihi.