MetService said a severe weather watch was in place for Northland, Auckland, Taranaki, Nelson, Marlborough, Buller and Fiordland due to expected heavy rain and strong northeast winds.
A strong northeast flow was expected to continue over northern New Zealand until tomorrow morning before easing. The system was preceded by a strong moist northeast flow bringing heavy rain to the north and west of the South Island.
The heaviest falls were expected in northern Fiordland, Westland and western Nelson.
Winds in Northland and northern parts of Auckland were expected to remain strong until then, with gales in exposed places and associated wind gusts of around 100km/h.
Northeast gales were likely in exposed parts of Taranaki from this afternoon through to Saturday afternoon. Winds could potentially reach severe gale strength, MetService forecasters warned.
WeatherWatch spokesman Phillip Duncan said windy weather would step up again across the upper North Island today as the final surge of stormy weather moved in.
The strongest winds would be around coastal and rural Auckland, the Hauraki Gulf, Eastern Waikato and western Coromandel Peninsula, and lower Northland.
Those winds would be blustery and could make driving tricky across the ranges and exposed highways, he said.
Auckland could expect a cloudy and mostly dry day with the exception of a few showers. Gusty nor'easters could reach gale force in exposed places, gusting to 100km/h, Mr Duncan said.
Later today those showers were expected to turn to patchy rain, he said.
Far North lines company Top Energy said around 3600 households in the region remained without power this morning, down from 6400 at 4pm yesterday.
The majority of affected households were in the north of the region, supplied from Kaitaia.
A fault remained on a 33,000 volt main feeder line in the part of the network supplied from Kaitaia which needed to be repaired before work could start on lower-voltage lines and feeder lines across the region. Top Energy expected to have the backbone of the network repaired by nightfall.
Repair crews continued to face difficult conditions. A high proportion of the region's roads remain blocked by flooding, and high winds and rain were expected again during the day.
Fallen trees also continued to make access to lines difficult but Top Energy was working closely with the Far North District Council and Fulton Hogan to clear them.
"Our lines staff have had to chop trees off roads just so we can get to the lines," Top Energy CEO Russell Shaw said.
Some of those currently without power faced a fifth or potentially even a sixth night without it, he said.
"I'm sorry to say that, at this stage, it looks like some customers may not have electricity until Sunday morning.
"We continue to work flat out. If you still have no power the important thing for you to know is that we know you're there and that we'll get to you as soon as humanly possible."
If affected residents were aware of any at-risk or seriously ill people who were suffering through the lack of power they should contact emergency services on 111 as soon as possible, Mr Shaw said.
"Any request for welfare, such as shelter, fresh water or food should be directed to the Far North District Council where it will be passed to Civil Defence."
Forecast
Whangarei: Rain, possibly heavy in the evening and gusts of up to 100km/h in exposed places.
Auckland: Occasional rain today with gusty northeasterlies.
Hamilton: Cloudy with chance of light rain.
Tauranga: Drizzly rain will develop by this evening
