Hawke's Bay recorded the highest temperatures in the country today, when the mercury rose above 30C.
Metservice recorded 30.5 at Napier Airport, 30 at Hastings and 29 at Napier City.
Dunedin City had the next highest at 29C.
Metservice forecaster Aidan Pyselman said the hot day in the Bay could be put down to northwesterly winds ahead of a couple of fronts moving across the country.
"When you get a good northwesterly blowing it often results in some pretty decent temperatures this time of year," he said.
Pyselman said it was the hottest January maximum temperature recorded in Napier over the past 15 years or so.
"The climatic average is about 24, so that's 7C above your average for this time of year," he added.
Hawke's Bay residents looking to cool off in the sea had to be wary over the weekend, with an easterly swell of 1.5 metres, easing to 1m this morning.
Metservice is forecasting a significantly cooler high of 25C for Napier tomorrow.