Many spots have been baked by temperatures above 30C today, as the scorching hot temperatures that kicked off the weekend continue.
The hot weather is expected to be interrupted with a few thunderstorms as the day progresses - keeping in line with the lucky dip of weather summer has brought so far.
Metservice meteorologist Kyle Lee said Wanaka had hit the peak temperature of the day, recording 32.5C at mid-afternoon.
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This was cooler than the 35.2C the region hit yesterday - the hottest day recorded there since records began.
Alexandra hit 30.8C and other spots in the south - Kawatiri (31.4C), Pupaki (30.9C) Manapouri (30C) weren't far behind.
Today's highs
Auckland - 28.5C
Hamilton - 29.7C
Tauranga 26.5C
Wellington 22.7C
Christchurch 25.6C
Dunedin - 27.2C
Queenstown 29.7C
Source: Metservice
Early this week those living in Central Otago had been told to brace themselves for temperatures of 40C and potentially even higher.
Thunderstorms were likely for the top of the South Island, down to Christchurch late in the afternoon and this evening.
The same thundery weather could hit western areas of the North Island, with a high risk of stormy weather around Hawke's Bay.
The Metservice has warned conditions were favourable for thunderstorms in Waikato, Waitomo, Taumarunui, Taupo, Taranaki, Taihape, Marlborough, Nelson, Buller, Westland and Canterbury High Country.
The combination of another very warm humid day and light winds has allowed daytime cloud buildups to produce scattered heavy showers and thunderstorms about the central North Island and inland parts of the South Island, the Metservice warned.
From 4pm to 9pm, some of those areas could see sever thunderstorms with localised downpours of 20-40mm in an hour.
The area has been baked by the scorching weather this summer.
Some of those working for earthmoving company Maungatua Contracting suffered heatstroke after toiling in the unrelenting Central Otago heat.
And this week, it will be another stinking hot day at work for project manager Kane Duncan's team.
But Duncan isn't expecting a repeat of heatstroke symptoms that struck some workers in December.
They had measures to combat the heat, even if some people learned the hard way about following advice to drink plenty of water.
"You only do it once, ay," Duncan told the Herald.
It's been a thumper of a summer — and a potential record-breaker with January likely days away from being the warmest month in New Zealand since records began in 1909 — with the heat arriving early and fiercely in November and barely releasing its sweaty grip since.
But early this week could be the fiercest of all, with the potential for the heat to reach 40C in parts of the South Island.
The southern part of the island, in areas such as Central Otago, would be hottest tomorrow; on Tuesday the worst of the heat could move further north, to areas such as inland Canterbury, Clark said.
After toppling its record with 35.2C, Wanaka, where Maungatua Contracting provides civil construction services, is forecast to reach 34C tomorrow and 33C the day after.
The Central Otago tourist town is in the middle of an official heatwave, considered to be when the daily maximum temperature is at least 5C higher than the average maximum for five consecutive days. Wanaka's average summer maximum is 24C.