An "early spring" storm is boosting temperatures into the mid 20s in what is normally the coldest time of the year, forecaster say.
The coastal town of Kaikoura hit 24C this afternoon, while parts of Canterbury, Hawkes Bay and Auckland recorded temperatures in the low 20s.
A strong northwester was the cause of the unseasonable temperatures, WeatherWatch said.
However, cooler air has already started to move into Southland and Otago, head weather analyst Philip Duncan said, meaning Sunday and Monday will be significantly cooler.
But not after a warm Saturday night for many of the main centres, particularly in the North Island.
"This is an incredibly warm spell for early August, but not surprising to WeatherWatch forecasters after a record-breaking warm June and plenty of mild westerlies expected this month," Mr Duncan said.
July was closer to average temperatures due to more southerlies blowing in cold air from the Southern Ocean, he said, in comparison to June which saw more northerlies feeding mild air from the sub-tropics over the country.
"A week ago people from Southland to Waikato were waking up to temperatures as low as -4C, this morning most woke up to temperatures 15C to 20C warmer," Mr Duncan said.
"Even Auckland was around 18C warmer this Saturday morning compared to last Saturday morning."
The bulk of the gales today are through inland, more rural, parts of the South Island, but winds are likely to rise further this afternoon in Wellington.
However, with the worst winds forecast around exposed areas, serious damage was not expected, he said.
The windy weather will ease gradually across Sunday as a band of rain moves over the North Island.
Sunday will be warm for many northern parts, but cooler air will spread across the South Island for Sunday and into the North Island on Monday.
Warmer spring-like westerlies are set to return around Wednesday, Mr Duncan said.
- Patrice Dougan of APNZ
