Weather warnings: Interislander cancels sailings amid strong wind ...

The swells were expected to ease by the afternoon and affected passengers had been moved to other sailings, it said.

It advised anyone who was worried about seasickness to sit at the back of the ship and they should not sail on an empty stomach.

Meanwhile, a heavy rain warning remains in place for Wairoa district until noon on Saturday.

MetService said people could expect 150-200mm of rain there, on top of what had already fallen, especially about the Wairoa ranges. Peak rates would be 10-20mm/h.

Strong wind watches remain in force for the following areas:

MetService warned southerly and southwest winds may approach severe gales in exposed places.

In a post on social media, it said large, powerful 4m southerly swells were impacting the south and east coasts of the North Island.

A heavy swell warning was in place for Wairarapa (Turakirae Head to Mataikona) until 8am on Saturday.

Big swells rising to 3-4m would be accompanied by large wind waves developing on Friday morning, MetService said.

These would gradually ease overnight into Saturday morning.

The highest risk period would be about high tide on Friday afternoon, the forecaster said.

– RNZ