"The high, also known as an anticyclone, will push in over much of the South Island today then much of New Zealand over the next 72 hours," WeatherWatch forecasted.
Yet the forecasters expected more snow to linger on the hills around Gisborne.
Nearly 1000 homes in and around Gisborne and Motu, 84km north, lost power after the big dumping of snow.
Gisborne's maximum temperature of 7C today was the fourth-lowest high on record.
Meanwhile, the last time it was so cold in parts of the coastal Hawkes Bay was in July 1990. Inland, Hastings only hit a high of 6.6C yesterday, the second-lowest high since 1972.
Anecdotal evidence from Wairarapa to Gisborne suggested some farmers hadn't seen snow so heavy in 30 to 60 years, WeatherWatch said.
The massive snowfall hindered the start of the economically important lambing season.
Sandra Faulkner, Federated Farmers Wairoa-Gisborne provincial president, said the effect on farmers would be huge.
"It will weigh heavily on farmers' minds and they will be keeping a very close watch on it over the next couple of days."
With the high pressure system arriving in most places tonight, WeatherWatch said Kiwis should expect heavy frosts nationwide in sheltered, clear-skied areas tomorrow morning too.
More hassle for motorists was expected tomorrow, with WeatherWatch warning black ice would remain a traffic hazard on rural roads this weekend.
Stretches of State Highways 1, 2, 4, 47, 48 and 49 were closed in the icy blast earlier today. One of the closed stretches of SH2 was at the Waioeka Gorge, a main route into Gisborne.
Several other roads in the Gisborne area were shut today and a fallen tree in Pehiri Rd meant access there was by 4WD only.
In the central North Island, the Desert Road was closed.
Greasy road conditions and snow were reported on other central North Island roads.
Towns outside Gisborne faced isolation as snow blanketed the region overnight and earlier today.
Colin Campbell at the Tiniroto Tavern, 59km southwest of Gisborne, said he had the busiest night for a long time, with about a dozen of 50 people stranded in the town staying at the pub.
"It was good as gold. We gave them a good feed last night and had a big sing-along," Mr Campbell said.
Local residents gave other stranded people in Tiniroto places to stay for the night.
Motorists were also stranded in Matawai on SH2 about 70km northwest of Gisborne.
Tonight, it would be cold in some major centres, but Auckland's predicted low of 4C was well above record historical lows.
In the South Island, severe frosts were expected in many alpine areas and MetService said Hanmer Springs was on track to reach an all-time record low of -12C.
People sick of wet weather may have cause for some celebration - MetService said showers in most eastern parts of New Zealand today would ease this weekend.
SATURDAY'S FORECAST:
Auckland: Fine with southerlies dying out. Low 3C, high 12C
Hamilton: Fine with morning frost and light winds. Low -3C, high 11C
Tauranga: Fine with morning frost and light winds. Low 4C, high 13C
Wellington: Showers dissipating with southerlies easing. Low 5C, high 9C
Christchurch: Cloudy periods with cold southwesterlies. Low -5C, high 9C
SUNDAY'S FORECAST
Auckland: Long fine spells with light winds. Low 4C, high 12C
Hamilton: Fine with morning frost, possibly severe, and light winds. Low -1C, high 12C
Tauranga: Fine with light winds. Low 5C, high 13C
Wellington: Fine spells with the odd morning shower and light winds. Low 4C, high 10C
Christchurch: Fine with severe morning frosts and northerlies developing. Low -4C, high 8C
(Source: MetService)
