Similar conditions are expected in the Tararua district from 9am today until 8pm.
Taranaki is still expected to bear the brunt of the rain, and a red weather warning has been extended to 2pm today.
"This rain is expected to cause dangerous river conditions and significant flooding. Slips and floodwaters are likely to disrupt travel, making some roads impassable and possibly isolating communities," MetService warned.
The forecaster urged people whose region was under a weather warning to keep up to date with information from local authorities.
Coromandel Peninsula, Bay of Plenty including Rotorua are both under a heavy rain watch from 10pm tonight and all day on Monday.
Waitomo, Taumarunui, Taihape, Whanganui and Manawatū are also under a heavy rain watch until 5pm, while Hawke's Bay from Napier and further south is under a heavy rain watch until 6am on Monday.
The rain comes from the same weather system that caused Friday's deluge in Westport and has brought tropical humidity to much of the North Island overnight.
Many people in the North Island would have woken up today feeling like they were in Fiji - if they managed to get any sleep at all, that is.
The humid weather, which has been hanging around over large parts of the country is expected to continue through the long weekend and into this week.
WeatherWatch analyst Philip Duncan earlier said overnight lows in northern New Zealand were forecast to almost match those in Fiji as tropical air moved south.
The humidity and temperatures would get more intense in the north, although cooler weather will come to the south.
Duncan said tropical airflows from the equator were drifting to northern New Zealand and this "thick air" - moisture-laden and humid - would push further down into NZ in the coming nights and the week ahead.
"The same combined airflows that produced the South Island deluge will move into the North Island now, triggering much-needed rain but bringing even higher humidity levels," Duncan said.
The humidity would make temperatures feel like the mid 30s in many northern parts of NZ, he said.
"Overnight lows will be especially tough for the next week ahead, but especially Sunday night and Monday night in the north with the humidex reading at 3am being around the late 20s or even 30C. It will feel more like Tonga or Fiji."
This will be more than 8C above average for parts of the North Island, while much of the South Island's interior will be 8C below normal as two different airflows affect the main islands.
MetService meteorologist David Miller said the same front responsible for flooding and the evacuation of hundreds of homes in parts of the West Coast of the South Island was moving across the North Island.
However, the intensity would be nowhere near what was experienced in the south.
"We're not expecting to see rainfall numbers anywhere near what Westland and Buller have seen. We got those phenomenally high numbers because that front basically stalled over the western part of the South Island and didn't move very fast," Miller said.
The heavy rain in Wellington, that started early yesterday, will gradually ease this morning.
Miller said much of the lower North Island would see "good heavy rain" after what had been a very dry January for most.
Heavy rain warnings remained in place for Kāpiti-Horowhenua and Wellington until 4am today, and the downpour was also expected along the Tararua Range 7am.
Taranaki also had a heavy rain warning until midday today with peak rates of 15 to 25mm/h about the mountain. Rainfall of between 180 and 250mm was expected to accumulate about Mt Taranaki, and between 80 to 120mm elsewhere across the region.
The heavy rainfall has led to warnings of possible flooding and slips from MetService, which could make driving conditions hazardous for those travelling over the long weekend.
There could be a slight break in the humidity for some next week, but this may not last long.
A large area of tropical low pressure next week will bring another round of humid airflows.
