Several homes in the Dairy Flat area, just north of Auckland city, have been evacuated after torrential rainfall from this afternoon's thunderstorms.
Auckland Civil Defence says Blackridge Rd has been particularly affected.
A shelter has been opened at the Dairy Flats Community Hall on Postman Rd, offering blankets, tea and coffee and food.
Earlier this afternoon, motorists in the area had to be rescued by boat after their vehicles became caught in floodwaters.
About 50 people are at the Mangawhai Gold Club Civil Defence centre north of Auckland tonight, caught out by heavy rain and road closures.
Further north, up to 30 students and their parents are reportedly stranded at a school in Northland after heavy rain caused flooding in the region.
Kaiwaka School put the call out for 30 blankets as students and parents prepare to hunker down for the night, according to social media reports.
Just south of Kaiwaka, more than 150mm was recorded inland of Mangawhai Heads. A Northland council rain gauge just outside Mangawhai measured a record 342mm for the day, most of it after midday.
Earlier, text alerts went out to residents in North and West Auckland to avoid unecessary travel as thunderstorms brought localised downpours.
Those in Rodney, Helensville, Upper Harbour, Te Atatu and Henderson Valley received an emergency alert on their mobiles this evening as the rain has increased the risk of landsliding and flooding.
Bethells Beach, Piha, Karekare and Muriwai, which have been cut off since Cyclone Gabrielle, have also received the the mobile alert.
The alerts come after Aucklanders were warned that two months’ worth of rain could fall in some parts of the region today.
Auckland's deputy mayor Desley Simpson said people in the areas should avoid all unnecessary travel.
Police say there are slips in north-west Auckland, especially in Mangawhai.
Meanwhile, heavy rain warnings remain in place for Hawke's Bay, Gisborne and the Coromandel, with the regions bracing for more downpours this weekend.
MetService says the heaviest rain for Hawke's Bay will be during Saturday morning with the risk of thunderstorms.
Auckland Emergency Management issued the alerts at 5.11pm due to the heightened risk of further landslides and flash flooding.
“The alert has been issued due to an active line of thunderstorms which has brought high intensity, localised downpours,” EMA said.
Earlier, Weatherwatch posted a message on Twitter that “one or two months’ worth of rain is going to fall in some places today (& already has done north of the city in rural areas)”.
Niwa meteorologist Ben Noll said a cold front that had been moving north had “stalled out” over Auckland, “and that’s going to act as a focal point for the development of heavy showers”.
“Auckland and Coromandel are certainly going to be under the gun here – and we’re concerned with the timing of this heavy rain coinciding with the afternoon and evening commute,” he said.
MetService said this afternoon the heaviest rain for Hawke's Bay would be during Saturday morning, with the risk of thunderstorms. Severe thunderstorm watches were also in place for parts of Northland, Auckland and the Coromandel.
Up to 40 homes in Napier's Esk Valley have been evacuated after an order, which took effect at 1.30pm today.
Emergency services were carrying out a sweep through the area to make sure everyone was safely out, Hawke’s Bay Emergency Management group controller Ian Macdonald said.
Macdonald said the order was a precaution, based on forecast rain and taking the condition of the Eskdale River into account.
"The timing is to ensure people can evacuate safely in daylight and before the impacts of the heavy rain make driving dangerous," he said.
"Once the order is issued, people must evacuate and not wait to go later, when roads are likely to be affected by surface flooding or slips."
Conditions were expected to improve on Saturday, and residents would be advised as soon as the threat had passed, so they can return to their homes.
North Island regions remain battered and soaked by Cyclone Gabrielle which hit on February 12, causing severe flooding to homes, businesses and damage to infrastructure, including main roads and bridges. Eleven people have died as a result of the massive storm.
- NZ Herald and RNZ
