Temperatures are forecast to top 30 degrees in many places, and heat alerts have been issued for Hastings, Napier, Whakatāne, Motueka, Blenheim and Kaikōura.
Fire and Emergency warned extreme heat came with heightened fire risk - particularly in Canterbury, Marlborough, Wairarapa, Hawke's Bay, Tairāwhiti and Northland.
Meteorologist Devlin Lynden said remnants from Australia's heatwave had arrived.
Photo: RNZ / Mark Papalii
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