The blistering heat in many parts of the country may be good news for some but is potentially disastrous for others.
MetService says the temperature reached nearly 34 degrees at Lake Pukaki in the central South Island at the weekend.
It was 31 degrees in several places including Masterton, Blenheim, Culverdon and Alexandra.
Fire restrictions are in place throughout the South Island, but Fire Service spokesperson Riwai Grace said firefighters were called to up to 70 unnecessary fires there during the 48 hours from midday on Friday.
He said some people were still lighting bonfires and fireworks, which could cause havoc.
In Otago, many farmers who take irrigation water from the region's main rivers have voluntarily reduced the amount.
Regional council chief executive Peter Bodeker said the restrictions had come about a month early. It could be a tough year for Otago farmers, he said, some of whom were already set back by a cold, wet spring.
Some farmers were already having to sell stock and could struggle to grow winter feed if there was no rain and irrigation was restricted, Mr Bodeker said.
However, the weather is good for Marlborough grape growers, with the moderate wind and lack of rain keeping the vines healthy.
Lake Chalice Wines owner Phil Binnie described the windy, dry, hot conditions as "pretty perfect".
MetService is forecasting scattered showers in some places early this week, but no significant rain.