Kiwis have woken up to the heaviest frost of 2016 in many parts of the country.

Temperatures have reached as low as -7 degrees C causing "severe" frosts in parts of Otago - including Cromwell and Dunedin, while parts of Canterbury got down to -4C.

And the North Island is not immune to the cold snap, with temperatures in parts of Waikato also dropping as low as -4C. Weatherwatch analyst Phil Duncan said it was the coldest morning so far for many places this year, with frosts stretching from Southland to Northland. 

Pretty chilly across NZ this morning. South Waiouru -9°C & Tekapo -7°C among coldest. https://t.co/hnwmGxU1gR ^PL pic.twitter.com/DtuTUkc7lG

— MetService (@MetService) July 1, 2016

At 7.45am it was 2C in Auckland, with a forecast high of 13C at 2pm, according to MetService.

He warned that some Auckland sub-tropical plant owners might find their specimens badly damaged or wiped out by frosts in parts of the city this morning. There are also heavy frosts around Rotorua and Taranaki, which are both down to -3C, about 7.30am.

Even Northland is down to -2C, with widespread frosts in sheltered inland areas. 

Kaitaia in the Far North was on just 1 degree C at 7.20am.

Duncan said more heavy frosts can be expected tonight, “especially in the North Island as the centre of the high (currently over the South Island) slides northwards.”

“But frosts may not be quite so heavy in some southern areas due to more cloud and a breeze developing overnight in some areas,” he said.