Roads remain closed north of Auckland and farmland is flooded as the region begins to mop up from yesterday's deluge.
The day of intense rain, which trapped people in homes and cars and left many roads impassable, will continue today but is not expected to be heavy.
MetService forecaster Mariken van Laanen said 130mm fell across the region in 24 hours.
Several roads in the Warkworth and Wellsford areas remain closed because of flooding, including Wayby Valley and Whangaripo Valley roads.
This morning a tree was blocking a lane on State Highway 1 south of Warkworth.
Although the rain has now eased, another 80-100mm is expected from 9pm last night to noon today. Peak intensities may reach around 15mm per hour.
State Highway 25 south of Coromandel Township is closed to heavy vehicles because of a slip.
One lane is closed and stop/go traffic management is in place.
Heavy vehicles can use State Highway 25A instead.
Geotechnical experts are assessing the slip today and the NZ Transport Agency advises motorists to expect delays.
Milford Rd, the main route to Milford Sound, could also be affected by bad weather. The area is expecting snow tomorrow morning, which will later turn to rain.
Van Laanen warned that although the rain had eased, it could still veer back to the peninsula, and a heavy rain warning remains in place.
Meanwhile, ice on overhead power wire services has disrupted train services across the Wellington region this morning. Several services were cancelled, and others were delayed for up to 30 minutes.
The South Island has also had a dose of wintry weather, and more wet weather is on the way, particularly for the West Coast.
A front is expected to move northeast over the South Island on Friday bringing significant amounts of rain to Fiordland and Westland. The rainfall could reach warning amounts.
Another front is expected to move northeast over the South Island on Sunday bringing significant amounts of rain to the west.
Main centres outlook
Whangarei: Today: A few showers, some possibly heavy or thundery this morning. High 16C. Tomorrow: Fine breaks and light winds. Northerlies develop. High 18C.
Auckland: Today: Mostly cloudy with a few showers. Easterlies. High 14C. Tomorrow: Fine breaks and light winds. Northerlies develop. High 16C.
Tauranga: Today: Cloudy with occasional showers. Gusty easterlies. High 14C. Tomorrow: Occassional rain developing in the morning. Northeasterlies. High 15C.
Hamilton: Today: Often cloudy, with a shower or two possible. Easterlies. High 14C. Tomorrow: Cloudy periods and a few showers. Winds turn northerly.
Wellington: Today: Morning frost then a sunny day. Late cloud. Light winds. High 13C. Tomorrow: Cloudy periods. Rain from afternoon. Northerlies. High 13C.
Christchurch: Today: Fine with morning frosts. Northeasterlies. High 11C. Tomorrow: High cloud with a few spots of rain later. High 14C.
Dunedin: Today: Fine with morning frosts. Northerlies. High 12C. Tomorrow: Few spots of morning and afternoon rain. Southwest change. High 11C.
- Source: MetService