Regions throughout the country have roasted today as scorching temperatures climb up and over the 30-degree mark.
Temperatures, especially in the east, reached at least 30C today and MetService is forecasting the hot weather is likely to continue.
Other maximum temperatures expected in parts of the North Island today were
25C in Auckland and Hamilton, 26C in Thames and 27C in Whāngārei.
In the South Island, Queenstown is set for 28C, while Dunedin escaped with a much cooler 22C.
The City of Sails is continuing a cracker Auckland Anniversary Weekend with clear skies and temperatures rising to a forecast high of 25C - perfect to see the performers at the International Buskers Festival around the Viaduct.
By lunchtime, the temperature will be well into the 20s.
People heading out for the many outdoor events today and at tomorrow's Laneway Festival are advised to use ample amounts of sunscreen, drink plenty of water and keep in the shade where possible. A high of 26C is forecast tomorrow.
MetService meteorologist Ravi Kandula said: "Essentially, a lot of the heat is going to be confined to the South Island, central parts of Otago - high 20s to the low 30s - Blenheim and Kaikōura.
"In the North Island, eastern parts - Gisborne, Napier, Hastings and Masterton. Those areas are going to get a drop in north-west wind and are going to get warm."
As well as needing a swim and an icecream, the heat could lead to more serious issues in the coming days. On Friday, the tar on State Highway 1 near Pūhoi, north of Auckland, started to melt.
MetService said a heatwave was defined by the World Meteorological Organisation as five or more days in a row of 5C above the average temperature.
The QIMR Berghofer Medical Research Institute - the body responsible for sun safety advice in Australia and New Zealand - has adopted a new policy of applying sunscreen daily following a summit in Brisbane last year.
An article published in the Australian and New Zealand Journal of Public Health on Friday said there was now clear evidence on the benefits of daily sunscreen use.
QIMR institute professor Rachel Neale, who co-led the research article, said incidental exposure to the sun happened daily, from activities like walking to the bus stop.
"In recent years, it has become clear that the DNA damage that causes skin cancer and melanoma accumulates with repeated small doses of sunlight.
"Up until now, most public health organisations have recommended applying sunscreen ahead of planned outdoor activities but haven't specifically recommended applying it every day as part of a morning routine," she said.
"The advice is now simple: make sunscreen part of your morning routine, just like brushing your teeth."
The heat over NZ begins to build from tomorrow! Christchurch is forecast to hit 30C tomorrow and 33C on Monday, whilst Blenheim is set to be one of the warmest spots over the next couple days; 34C and 35C forecast! Check how hot it will get for you @http://bit.ly/metservicenz ^JM pic.twitter.com/LSYkirszEV
— MetService (@MetService) January 26, 2019
While many of the findings were related specifically to Australia, the advice was also applicable to New Zealand.
Craig Sinclair, the Cancer Council Australia's prevention adviser, said adoption of this advice could lead to a reduction of skin cancer rates in the future.
Another worrying thing that cropped up from the research was that nearly half of Australians believed sunscreen could not be used safely on a daily basis.
Dr Stephen Shumack from the Australasian College of Dermatologists said it was important people continued to use other forms of sun protection, if planning on spending longer periods of time outdoors.
"People need to remember that sunscreen isn't a suit of armour," he said.
"If you're planning outdoors activities – like playing or watching sport, going fishing or working outdoors – you should also seek shade, wear a hat, protective clothing and sunglasses, and reapply your sunscreen every two hours."
New Zealand has the world's worst rates of deaths from malignant skin melanoma at 6.6 per 100,000 people - around six times the global average.