Thursday morning has been the coldest of the year so far, with frosts reported as far north as Waikato.
Temperatures in Hamilton dropped to zero degrees and Palmerston North and Timaru both recorded one degree at 7.30am.
Waiouru recorded minus three and Taupo was on zero.
Parts of Auckland fell to seven degrees while Dunedin had two.
Christchurch was on four and Wellington fell to eight.