A predicted heatwave has public health officials warning people in Otago and Southland to look after themselves, and others.
Temperatures in many places are expected to top 30decC for the next several days.
Waiau, in Northern Canterbury, hit a blistering 37degC yesterday, the hottest temperature recorded for New Zealand in seven years.
The record temperature for New Zealand was measured in Rangiora in February 1973, when it reached 42.4degC.
On Monday, the temperature is forecast to hit 35degC in Alexandra and Cromwell and 34degC in Wanaka.
That news prompted the Southern District Health Board's public health team to urge the public to keep as cool as possible.
Hot temperatures last week resulted in several people, mainly elderly, visiting Southland Hospital's emergency department for help.
Outdoor workers should consider changing their hours so they are outside only early morning or later in the day, to take advantage of cooler temperatures, and hats, sunscreen and shirts will be essential.
"Older people, children and those with underlying medical conditions are most at risk of the impacts of heat stress," medical officer of health Keith Reid said yesterday.
"We also ask you to check that vulnerable neighbours are doing OK.
"These might be older folks or those with medical conditions that might make them more susceptible to the effects of heat."
While reaching for a cold beer might seem the ideal thing, Dr Reid warned alcohol speeded up dehydration.
"People should have regular fluid intake — at least two litres of water a day — and stay out of the sun.
"People can keep their houses cool by opening windows to get a breeze, closing curtains to keep the sun out, and consider using the cool cycle on heat pumps."