''We have this very, very cold southerly outbreak moving through the country,'' Mr Little said.
''The air has come up from down south, pretty much Antarctica, and is moving north across the country. A low-pressure stream pushed a lot of rain and snow into the Hawkes Bay area and now that low is driving north east.
''However, the Bay of Plenty is nice and sheltered but the cold air still lingers. That's why the days are quite cool and we are seeing a lot of frosts.''
Readers were quick to share how cold it was at their place, with several posts to the Bay of Plenty Times Facebook page including Robyn Matthews-Hunt recording -3.4C at her Pyes Pa home and Nicole Harvey recording -2.1C in Te Puke at 6am.
Kerri Anne Fraser recorded -3C near Papamoa Hills.
''Biggest frost for us so far this year,'' she said.
The polar blast that has swept through New Zealand has brought snow to much of the central North Island, prompting slips and road closures.
State Highway 5 between Napier and Taupo was closed on Sunday due to heavy snow and it remained closed overnight.
The NZ Transport Agency were expecting to readdress the possibility of opening the highway at 10am today.
Communities and farmers on the snow covered Taupo Plains were being warned to expect to be without power for more than a week.
Power network for Hawkes Bay Unison said its network had been devastated by the weekend's wild weather with 200 poles broken, twisted and buried under a metre of snow.
Tauranga's coldest days of the year
July 1C
June 3C
May 7C
April 8C
- Metservice