Alongside the high temperatures MetService said this is going to be a week full of "lots of sun" throughout the day in Northland, with morning and evening cloud.
MetService Meteorologist Tui McInnes said that the heatwave is caused by hot air moving over a warmed up Tasman Sea.
"As the air moves over the Tasman Sea, it stays warm. Combining this with calm and settled conditions due to a high over New Zealand, the sun is able to knock those temperatures up a few more degrees."
McInnes urges that with these "hot temperatures and scorching sun" it is important that people are sun smart, hydrated and keep an eye out for vulnerable members of the community, including pets.
MetService said a minor temperature change will occur over the weekend, with slightly cooler temperatures forecast.
"Temperatures aren't expected to drop drastically, but expect warm temperatures, rather than hot."