The severe storm that has toppled power lines and trees in Northland has forced the closure of Whangarei's central business district.
Police officers and fire crews are helping to clear the area, which is closed until further notice. A series of severe wind gusts caused damage in the Port Road area, tearing down power lines and rolling over containers.
Whangarei's civil defence is asking people to avoid going outside, and drivers to keep off the roads, with widespread flooding on low-lying coastal areas, including the Whangarei Heads and Ngunguru roads.
Wind gusts of up to 165 km/h were recorded before midday at Cape Brett in the Bay of Islands.
Mt Ruapehu skifield spokesperson Mike Smith says the storm hit a little earlier than predicted, and up to 10,000 people were told to leave the mountain.
Police and mountain staff are dealing with cars stuck in blizzard conditions in the Mt Ruapehu area, and the Desert Road was closed at 1.30pm due to snow.
National Park police say two-wheel drives are finding it extremely hard to make their way down from the skifields which which shut at 10.30am when the storm hit.
Police say a few motorists were still trying to make their way up the mountain on Saturday afternoon, and they need to get out of the area.
At least 1,000 homes in Northland are without power as high winds and heavy rain lash the region.
Volunteer crews have been called out from Kaitaia, Kohukohu, Mangonui, Paihia, Kerikeri, Dargaville, and Omapere, and have been securing roofs.
Fire Service Northern Communications has received reports of trees coming down across roads, as well as roofs lifting from at least four houses in Omapere.
Power company Top Energy is reporting widespread outages across the Far North, including Kaitaia, Opononi, Taupo Bay and Coopers Beach.
North Energy linesmen are also working on restoring power to around 400 homes at Whangarei Heads.
The weather system as brought heavy rain, with 70mm recorded in Kerikeri and 45mm in Whangarei on Saturday morning.
Metservice is predicting the storm will last about 24 hours. It says the wind will be strongest in Waikato, Taranaki and the King Country, while the north and east of the North Island will get most of the rain.
Civil Defence centres in the North Island have warned people to be prepared in case of flooding or power outages. Auckland's Civil Defence headquarters is being staffed from Saturday afternoon.
Lines company Vector is warning people on emergency medical equipment to be prepared for power disruptions. It says power lines may fall, cutting supplies or creating a hazard.
The Coastguard has told Auckland boaties that if they have not already checked their moorings it is too late to do so, and they should not risk their lives by venturing out.
Duty officer Mark Leevers says a number of boats have already slipped their moorings in the Waitemata Harbour, due to strong wind gusts, but owners should stay on shore.