A large high pressure system over New Zealand is likely to bring temperatures as high as 28 degrees this week, especially in eastern areas like Hawke's Bay.
The unseasonable spring heat is likely to begin building today and peak tomorrow in many areas, before giving way to a colder, wetter front coming up from the south on Thursday and Friday, MetService reports.
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That band of rain could bring heavy downpours to many parts of the South Island including the West Coast and the top of the island around the Marlborough and Tasman areas.
NIWA meteorologist Ben Noll last week said the heat is building early this year in part due to the onset of El Nino conditions.
Mr Noll added our oceans could also be great for swimming by later this month, with water temperature warmer than usual for this time of year.
Meanwhile, the strong winds that have affected much of the country are due to being dying down today.
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