The Wellington suburb of Kelburn has had its hottest day on record, reaching 30.3C today, following on from yesterday's record-breaking heat in Richmond.
Forecasters predicted the hottest temperatures would hit the central North Island and by 10am - Kawerau had already reached 29C.
It's been so hot lately that icecream parlours have been struggling to keep up with demand and freezers are straining to handle the heat.
"Kelburn has one of the longest and highest quality temperature stations in New Zealand, it's a lovely grassy enclosure on the top of the botanical gardens. It has not been modified in the 90 years of record and today it broke its all-time temperature record, recording 30.3 there today," MetService meteorologist Georgina Griffiths told Checkpoint.
'It's a really notable hot day today for Wellington' - Meteorologist Georgina Griffiths
She said wide-spread was the key to the heat at the moment.
"We actually saw a few records in Auckland tumble, we had 30 degrees in many of the suburbs inland away from the coast where the seabreeze couldn't get to, to cool things off."
Over 30C degrees was pretty notable, she said.
"Five days of heat guys, we're only in day two."
She said which day would be the hottest depended on where you were.
The East Coast of both the South Island and North haven't seen the worst yet, she thinks.
Fog at Wellington airport today, which has grounded flights until midday. Photo: RNZ / Rob Dixon
Flights in and out of the capital this morning were grounded because of dense fog and some ministers missed the beginning of this morning's first Cabinet meeting of the year.
In Northland, where there is a total fire ban, Fire and Emergency have been battling scrub fires, and just today parts of Canterbury have moved to a restricted fire season meaning permits are required.
Beach goers in Wellington taking advantage of the hot weather. Photo: RNZ/Rebekah Parsons-King
DHBs aren't reporting any significant increase in people presenting for heat-related illness, medical experts are still urging people to be careful and take the heat seriously.
Medical Officer of Health Alistair Humphrey said people should stay out of the sun where they can and drink plenty of water.
"Your urine should be a kind of chardonnay colour, a sort of very pale yellow - if it goes orange you're not drinking enough. Make sure you avoid alcohol because alcohol will dry you out.
"Please don't leave pets or children in the car, even for short periods of time because as soon as the engine's off it's like an oven."
He said heat could kill if not managed properly.
"In Europe in 2003 more than 70,000 people died as a consequence of a heatwave. We don't want people dying so we need to look after each other and ourselves."
He said those most vulnerable were the elderly, small children and people with a chronic disease.
"They often will not know if they are suffering from the early signs of heat stroke they may be getting a little bit dizzy or developing a headache, they may look a little bit flushed.
"So if you're with someone who you know may be vulnerable and they're not looking to well make sure they're drinking enough and that they're staying cool."
The heat is expected to last a few more days, but forecasters say there should be some reprieve on Friday.
But remember, if you're planning on cooling off in water you may want to rethink packing that giant inflatable swan for the kids.