Down the road in Invercargill, the temperature was 12C at 7am.
Those in the central North Island should be so lucky.
Chilliest overnight was the Desert Rd, where the temperature dropped to -4.9C, and Waiouru, where the low was -3.7C.
Hamilton was the coldest of the main centres, on -2.7C overnight, and it wasn't much better in Rotorua, where -2.4C was recorded, Little said.
Even Auckland, used to mild winters, dipped below zero - by half a degree at Whenuapai and 0.1C at Ardmore.
Not everyone was sympathetic.
Wind and cloud had protected Wellington from a frosty night, giving the city an overnight low of 12C, but those in the capital shouldn't expect a warm day.
"It's warming only slightly more today. I think we'll be lucky to reach [the forecast] 15C," Little said.
It was better news for those in the top half of the North Island.
Today will be chilly - in Auckland the mercury will nudge 15C - warmer weather is on the way. Our biggest city will bask in daytime highs of 18C for the next four days.
"The outlook is for warmer weather. Wednesday and Thursday is not looking too bad."
No weather warnings are in place across the country, but there are watches for heavy rain in Westland and severe gales in Otago, Southland and Inland Canterbury today.
AUCKLAND
Today: Fine, cloud increasing. 15C
Tomorrow: Partly cloudy, few showers developing. 18C
HAMILTON
Today: Cloud increasing, a few showers late at night. 14C
Tomorrow: Mostly cloudy, a few showers. 16C
TAURANGA
Today: Fine, cloud from afternoon. 15C
Tomorrow: Partly cloudy, a few showers. 17C
PALMERSTON NORTH
Today: Mostly cloudy, a few showers from afternoon. 14C
Tomorrow: Mostly cloudy, a few showers. 15C
WELLINGTON
Today: Mostly cloudy, the odd shower. 15C
Tomorrow: Mostly cloudy, a few showers. 14C
NELSON
Today: Cloudy periods, odd shower from afternoon. 14C
Tomorrow: Fine, apart from morning cloud. 15C
CHRISTCHURCH
Today: High cloud, odd shower late evening with southerly change. 17C
Tomorrow: Cloudy periods, chance morning shower. 12C
DUNEDIN
Today: Cloudy periods, the odd shower from afternoon. 15C
Tomorrow: Mainly fine, some morning cloud. 12C