KEY POINTS:
Emergency services were last night preparing for a big slip which they feared could wipe out a street of homes on the North Shore.
Police evacuated dozens of people from 15 houses in Lingham Cres, Torbay, after yesterday's storm left a 12m split in the ground.
The brutal weather over the past five days has killed at least four people and cost the country more than $10 million.
More rain and destructive winds are expected throughout the country today.
The storm hammered the North Island yesterday, closing dozens of roads, flooding properties and causing numerous slips, evacuations and widespread property damage.
It cut power to tens of thousands of homes nationwide, and many were still without electricity last night.
One of the houses in Lingham Cres, at the top of a slope above dozens of other properties, was described as "twisted" and had severe cracks in its foundations.
Firefighters stayed at the scene overnight in case the house collapsed and carried other homes with it down the slope.
"There's one house that's uninhabitable - it will be a write-off," said David Keay, from North Shore Civil Defence.
"There are cracks in the foundations, major cracks in the driveway. The frame has twisted and snapped in places, it's in a higgledy-piggledy fashion.
"It's so distorted it looks like a crazy house. It's not a pleasant sight,"Mr Keay said.
"It's holding up a lot of debris and water. If it goes, it could possibly take out two or three other houses and then pour into another 11 houses."
Another two houses had severe cracks and could collapse.
Residents were given a few minutes to gather important possessions before leaving their homes.
Officials said it could take days before they were able to go back.
Throughout the North Island and upper South Island yesterday, tens of thousands of households were left without power.
Several towns, including Tairua and Pauanui, were cut off as roads flooded.
The small settlement of Manaia, about 12km south of Coromandel, was inundated.
In the 24 hours to midday yesterday 310mm of rain - more than a quarter of Auckland City's yearly rainfall - was recorded near the Karangahake Gorge.
Flooding and slips closed the gorge to traffic for most of the day.
A small tornado at Mt Maunganui wrenched roof-tiles off houses, while east of Tauranga, three Omokoroa Peninsula homes were evacuated because of slips.
A house at Te Awanga in Hawkes Bay was washed away when the land it was on collapsed into heavy seas.
Railway lines, including the North Island main trunk line near Te Kauwhata, were closed for long periods yesterday as Ontrack struggled to clear trees, power lines, smashed barrier arms and slips.
Auckland passenger trains ran about 30 minutes late for much of yesterday morning after an extreme-weather speed restriction of 40km/h was imposed.
Flooding was reported in many places between Blenheim and Kaikoura yesterday afternoon, as the storm swept south.
Overnight the storm was hitting the top half of the South Island. Heavy rain warnings were issued for the region, and gales of up to 140km/h were expected in parts of Nelson, Marlborough, Buller and Westland.
Search and Rescue staff in Nelson were last night preparing to go into bush near the Kahurangi National Park to rescue four trampers cut off by the swollen Wangapeka River west of Nelson.
Four members of the group of eight crossed the river to safety, but the remainder later activated a distress beacon.
Torrential rain meant helicopters could not be used so rescuers were preparing to go into the area in darkness last night, a Rescue Co-ordination Centre spokesman said.
The storm knocked out an important water pipeline in Nelson, and the Marlborough District Council declared a state of emergency.
Picton police and volunteers sandbagged the waterfront in an effort to save the town from flooding.
The town's Cook Strait ferry terminal was shut because of flooding.
High winds closed SH6 at Whangamoa, between Nelson and Havelock.
The Chathams were expected to be hit by heavy rain and gales overnight.
The Canterbury foothills are expected to receive the bulk of today's rain - up to 140mm.
Federated Farmers president Don Nicolson said bad weather was always a blow to farmers, but they had been well warned of these storms.
Insurance Council chief executive Chris Ryan said it was too early to tell what the financial cost of the two storms would be, but insurers were waiting for reports of damage. The bill from the foul weather would "very comfortably" top $10 million.
As the rain continued to fall in already water-logged areas, the potential for houses or other structure to slip was very real, he said.
The National Institute of Water and Atmospheric Research yesterday said further storms were likely until October, although rainfall nationwide was not likely to be above average.
WHAT'S COMING
Today: Strong westerly winds and showers for the North Island, heavy rain and severe gales in the south.
Tomorrow: Showers over most of the country. Strong winds continue.
Saturday: More showers for northern and central New Zealand. Expect showers at Eden Park.
