Shortly before 2pm Oamaru was sitting at 30.1degC with Dunedin a balmy 28degC.
Dunedinites would be advised to enjoy the heat while it lasts as rain is forecast for later in the afternoon accompanied by falling temperatures.
MetService meteorologist Michael Pawley said the weather over the next few days would be like "a seesaw", conditions bouncing back and forth from hot to cool, dry to wet, and windy to calm.
Mr Pawley said, on top of the heat, the strong northwesterlies were expected to rise to gales this morning, gusting to 100kmh.
Some showers were expected in the evening.
Fenz community risk manager James Knapp, of Dunedin, said given the forecast high temperatures and strong winds, the fire danger would be high today.
He again cautioned residents to avoid doing anything that could generate a fire.
He said there was a spate of fires during very hot and windy weather at the end of last month, and firefighters were kept extremely busy putting out more than a dozen vegetation fires across Otago and Southland.
"Nothing really has changed in terms of the fire season at this stage.
"We’re just hovering around the thresholds for a season change.
"It’s still an open fire season for most of the district, but people still have a legal responsibility to make sure that any fire they do light remains under control and is fully extinguished."
He urged people who had had a fire on their property recently to visit it again this morning and make sure it was not still smouldering.
Mr Pawley said tomorrow would be drier, calmer and cooler again, temperatures only reaching the high teens or early 20s.
On Sunday morning, the foehn winds would return again, making for very warm temperatures along coastal and central Otago.
However, in the afternoon, a front, preceded by a strong northwesterly flow, would move northeast over the lower South Island, bringing warning amounts of rain to Fiordland, Western Southland and about the headwaters of the Otago lakes and rivers.
There would also be downpours for the rest of Southland and Otago, which would continue into early Monday morning, he said.
"It’s real seesaw-type weather."
