Communities in Northland have been isolated as roads and bridges were washed out in heavy rain, which battered coastal parts of the region overnight.
MetService said there had been "significant flooding" in coastal parts of Northland this morning, with up to 200mm falling over the eastern hills north of Whangārei.
Earlier, Northland was under an orange heavy rain warning, with Auckland under a heavy rain watch.
Both advisories had since expired, though heavy rain watches for Great Barrier Island, Coromandel Peninsula, and Gisborne about and north of Tolaga Bay remained.
Up to 200mm of rain fell across the region overnight, with Civil Defence Northland saying the east coast "took a hit". (Source: Supplied)
Civil Defence Northland said the east coast had "taken a hit" from the edge of the current cell moving through.
"There has been extensive flooding affecting the east coast of Punaruku, Ōakura and Ngunguru. The roads to Punaruku, Ōakura and Ngunguru have been closed due to surface flooding and land slips."
Tuparehuia Marae, Ngaiotongo Marae, Otetao Marae and Mokau Marae had opened up for people to evacuate to, the statement added.
"Campgrounds are also open, but are supporting tourist and local whānau in the immediate area."
Have you been affected by the weather? Send photos and videos to news@tvnz.co.nz
'We weren't warned': Knee-deep flooding catches Ōakura off guard
Ōakura resident Doug Hanna said the flooding hit in the early hours of Sunday morning, with many locals sleeping through the danger.
"We were woken at 2.30am by incredibly heavy rain … it didn't let up until after 7am so it just went on and on and on," he said.
"We've had flooding before, but never this bad."
Hanna went door-to-door between 5am and 6am, waking neighbours whose cars were close to being submerged.
"Everyone just thought it was heavy rain. None of them realised it was flooding until they looked outside."
He told 1News that floodwaters had since dropped significantly, but at their peak were knee deep in some areas.
"We had a forecast that was going to be wet, but we didn't anticipate such a huge amount of rain so hard and fast, everyone was very surprised.
"We just weren't warned of it really."
Amy Tipene told 1News she was heading to Auckland for her son's football academy when she came across flooding at Scows Landing, between Ngunguru and Whangārei.
"It was pretty scary as the river was breaking its bank and still rising," she said.
Whangārei District Council said surface flooding in the Ōakura and Ngunguru closed roads and may have isolated communities.
"Do not attempt to travel in or out of Ngunguru, Helena Bay, Ōakura, Punaruku or Whangaruru until rain and flooding clears."
Vinegar Hill Rd, Russell Rd, Ohawini Rd, Whangaruru North Rd, Whangaruru Wharf Rd, and the Old Russell Rd were among the blocked or closed roads. Road access would "take some time" to restore, the council added.
Lines company Northpower reported around 750 properties without power as of 10am.
The areas of Ngunguru, Helena Bay, Ōakura, Punaruku and Whangaruru have been cut off by flooding, a Whangarei District Council spokesperson said.
"Please do not attempt to travel in or out of these areas until rain and flooding clears."
Police said motorists are advised to avoid travel due to flooding and slips between Whangaruru and Helena Bay.
"Police have received multiple calls this morning, reports of intense flooding and slips in the Whangaruru, Oakua, and Helena Bay areas, especially on Russel Rd.
"Thankfully, at this stage there are no reported injuries. Motorists are advised to drive to the conditions and delay travel where possible.
Whananaki Civil Defence will open the fire station for anyone who needs support, according to the district council.
SHARE ME