MetService warns intermittent rain will add to the city's humidity. Photo: RNZ/ Mohammad Alafeshat
Metservice has updated Thursday's record temperatures in Auckland to 27.1°C.
Metservice said it is the highest November temperature recorded at their Auckland Airport station since records began.
It was a sweltering day across much of the country, with temperatures also exceeded 30°C at Christchurch Airport for a second consecutive day while 33.0°C in Hastings was the day's hottest spot.
On Wednesday, Whanganui Airport reached 27 degrees - equal to its November record.
MetService meteorologist Lewis Ferris said MetService's temperature records for the Auckland region began on 31 December 1965.
"With record or near-record temperatures turning up in parts of the country, it's not too surprising to see Auckland actually get up there as well, because a lot of these temperatures are being driven by very warm, humid air being dragged down from the north," Ferris said.
"Auckland being closer to there, they are going to be feeling those effects and people have probably been wondering why it felt so swampy, so humid the last couple of days.
"It is that warm, humid air being dragged down, and it does look to hang around, as we make our way through the rest of this week and into next week.
"There will be some intermittent rain as well, so it is just going to make it feel a little bit more humid."
A Transpower spokesperson said there was evidence energy usage was high in Auckland.
"We can see around 100MW of additional load across the Auckland region that we can reasonably confidently attribute to an increase in electricity demand in response to the record temperature, for example additional air conditioning."
"That's an increase of around 10 percent of the demand we'd expect to see across the region on a weekday at this time of year."
Ferris said sea-surface temperatures to the northwest were already above average and similar windflows would likely make its way to New Zealand in the coming weeks.
"These warm, humid days could be something we see a little bit more of, as we head through December.
"Won't be warm every day, though. You know, December is a little bit of a copout, when it comes to summer.
"There probably will be some cooler southerly air, but I think holding onto these days and thinking that they will be more of them as we make our way through December is probably not a bad idea."
Ferris said warm, humid air did provide a good amount of low-level moisture, which could turn into afternoon showers and potentially thunderstorms.
"Conditions in the upper atmosphere aren't always ripe for that kind of stuff, so people will need to be keeping up with the forecast to see if those showers are going to be turning up in the afternoon.
"You might think it's a lovely day, it's warm, let's get out the barbecue for the evening and that could just be when some of those showers turn up."
Sign up for Ngā Pitopito Kōrero, a daily newsletter curated by our editors and delivered straight to your inbox every weekday.
