MetService meteorologist Gerard Bellam told the Herald swells as high as 2.5m were forecast across the east coast from Northland to the Bay of Plenty.
The conditions were expected to last throughout the Easter weekend.
Bellam said “quite dangerous conditions” were also expected on the west coast from Saturday as a westerly swell from the weather system runs from 90 Mile Beach down to Taranaki.
Waves run over the foreshore at Helena Bay, northeast of Whangārei central, at high tide on Thursday morning. Photo / Denise Piper
Bellam advised people to “just be cautious” over the weekend, especially if they were staying in popular east coast destinations such as the Bay of Plenty, the Coromandel and Great Barrier Island.
Safeswim marked dozens of beaches across the northern regions as unsuitable for swimming on Friday afternoon, including Browns Bay, Titirangi Beach and St Heliers in Auckland.
After delivering a hit of rain and wind to New Zealand, the cyclone continues to direct unstable fronts and troughs on to the country.
Tasman, Nelson and northern Marlborough should expect some heavy falls on Saturday, while Auckland will likely receive scattered rain that could turn heavy.
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Reporter Martha and friends are in Minginui introducing us to their favourite four-legged neighbours, wild but friendly horses that have had free reign of the place since 1870.