Metservice says parts of Waikato will be hit by what's expected to be the last of today's wild weather.
It says the poor weather is a typical late-autumn storm and should not last more than a day or two.
As a storm swept across the country this morning, a fire at a house in Matakana Road, Warkworth, was started when rough weather caused power lines to arc at the property.
Further south, a macrocarpa tree fell on a house in Oruanui, near Taupo, but emergency services said no one had been injured.
In Northland, intense rain led to areas of flooding in Coopers Beach and surface flooding on State Highway 10 in Mangonui.
Metservice said after 2pm the worst of the wild weather that had plagued much of the country had passed.
Torrential rain hit much of the North Island this morning including the Bay of Plenty region, the Far North and Manawatu.
Buller in the Tasman District was also subject to thunderstorms.
The police say flooding on roads has already caused three car crashes today in the greater Wellington region.
Motorists travelling on State Highway 8 over Burkes Pass between Fairlie and Tekapo are were told snow chains would be required and the road was closed to towing vehicles.
It snowed in Arthur's Pass this morning and Metservice said about four centimetres more would fall this afternoon, but chain restrictions through State Highway 73 were later lifted.
Parts of Manawatu Gorge road were blocked by slips brought down by heavy rain. Two slips came down within 150 metres of each other, bringing traffic down to one lane in some areas and causing delays for motorists.
Car crashes in Wellington and Kapiti this morning were blamed on heavy rain and treacherous roads.
A three-car smash involving a head-on collision on SH1 at Paekakariki left one person with serious leg injuries. A car went off the road in Pauatahanui and another hit a pole on State Highway 2 near Lower Hutt.
A section of the shopping centre at Johnsonville in Wellington flooded but the mall remained open. Surface flooding was reported on SH1 near Churton Park.
In the South Island, Golden Bay had heavy rainfall including including 65mm in one hour at Anatoki and 53.7mm at Collingwood between 1am and 2am causing some flooding.
SH60 between Riwaka and Takaka was reduced to one lane due to a number of slips.
There was some surface flooding in Motueka. However Nelson and Tasman civil defence said river levels in the district had receded as the band of heavy rain moved away.
MetService said today's localised downpours and northerly gales were brought in by a low-pressure system moving across the country.
"A big active rain band over the North Island and also wrapping around into Canterbury as well and strong winds, gales in some places, associated with that as well," MetService meteorologist Stephen Glassey said.
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