The big freeze should ease slightly in days ahead but cold weather is straining social services in Canterbury just as floods test the resolve of central North Islanders.
WeatherWatch head analyst Philip Duncan said showers were lingering around Gisborne and Hawkes Bay - remnants of the system that pounded Whanganui and Taranaki in recent days.
Mr Duncan said that system had "stalled" east of the country so the eastern fringe of Northland could also expect showers to continue.
"But most other places are enjoying stunning weather," Mr Duncan said. "And Auckland is also having especially sunny weather ... we've got mostly sunny skies today and again tomorrow."
More frosty conditions were expected for many Kiwis over the next day or two, but the west will be best for sunny weather.
But first, it might be wise to prepare for a cold night tonight.
"The overnight lows tonight are going to be pretty brutal for some areas. They're severe," Mr Duncan said.
"It's going to stay cold for the next couple of days ... because winter's here and the gate's open to the polar air now," he added.
"So once it arrives it's sometimes quite hard to just get rid of again without a big tropical system. So the temperatures creep up, but they only creep up a little bit."
WeatherWatch said "severe morning frosts" were possible tomorrow, mainly in inland areas.
Mr Duncan said frosts should ease after Friday.
Freezing weather was driving a surge in bookings to tropical holiday destinations, one travel agent said.
In the past fortnight, local bookings to Queensland, Fiji and Indonesia jumped as much as 300 percent, said Dalwyn Sinclair of Upper Riccarton House of Travel.
For those without the money to travel, the reality was grim.
The latest big freeze left Christchurch's post-earthquake homeless population in a rut - not just rough sleepers but people dossing in garages, cars, and broken houses.
Christchurch City Mission's night shelter, which could house seven women and 30 men, was at full capacity last night.
The Mission put on an extra women's bed because of the cold nights.
The Salvation Army was handing out extra blankets and heaters.
Many Cantabrians were suffering in silence, living in sub-standard private rented accommodation, too scared to complain for fear of being evicted, many organisations said.
"We are only seeing the tip of the iceberg here," said Helen Gatonyi, manager at Christchurch Tenant's Protection Association, referring to the homeless on the street.
Mr Duncan expected Christchurch to dip to -4C tonight and about -3C tomorrow night.
MetService expected temperatures in the city to plummet to -5C tomorrow night, far colder than even Dunedin.
THE WEEK AHEAD:
WEDNESDAY
Auckland: Sunny. Morning frost in sheltered places. Southerlies. Low 7C, high 12C.
Hamilton: Sunny. Morning frost. Southerlies. Low 1C, high 11C.
Wellington: Showers clearing afternoon, then cloudy. Southerlies. Low 6C, high 10C.
Christchurch: Fine and frosty with light winds. Low -5C, high 8C.
Dunedin: Fine, with morning frosts and light winds. Late cloud. Low 3C, high 8C.
THURSDAY
Auckland: Fine spells. Fresh southwesterlies. Low 7C, high 12C.
Hamilton: Fine, morning frost. Southwesterlies. Low -1C, high 12C.
Wellington: Mostly cloudy. Fresh southerlies easing.. Low 6C, high 11C.
Christchurch: Fine spells, morning frost. Light winds. Low -5C, high 10C.
Dunedin: Mainly fine, morning frost. Light winds. Low 2C, high 8C.
FRIDAY
Auckland: A few showers. Southwesterlies. Low 10C, high 15C.
Hamilton: Mainly fine, morning frost. Late showers. Southwest. Low 5C, high 15C.
Wellington: Cloudy, late rain. Northwest changing strong southerly. Low 7C, high 14C.
Christchurch: High cloud, northerly. Showers later, southwest change. Low -2C, high 14C.
Dunedin: High cloud, northerly, then showers, southwest change. Low 3C, high 11C.
(Source: MetService)