Motorists were stranded in swamped vehicles and more than a dozen homes were awash after a storm cell unleashed a torrent of rain on an Auckland suburb this morning.

The storm cell, which hit Rosedale on the North Shore just after 8am, caused an hour of chaos as roads turned to rivers and spilled into business and homes.

Flooding on Caribbean Dr, Unsworth Heights. (Photo / Kirsty McAlpine)

Two motorists needed rescuing from their vehicles after they became submerged in the waist-deep floodwater.

A section of Carribean Drive was closed and lanes on the Upper Harbour Highway were blocked by the quickly rising floodwaters.

Niwa said an incredible 62.4mm of rain fell between 8am and 9am - the wettest hour in at least eight years - as the slow-moving storm cell delivered a deluge over the northern suburb.

Cars stuck in floodwaters in Albany. (Photo / Michael Craig)

Fire and Emergency northern shift communications manager Scott Osmond said firefighters rescued people from two cars that got trapped in floodwaters on Rosedale Rd and Caribbean Drive.

About 14 homes were affected by flooding and firefighters cleared blocked drains to help the water drain away.

#Auckland's North Shore (Albany) observed an incredible 62.4 mm of rain in one hour between 8:00-9:00 am. This was the wettest hour in at least 8 years. So far today, the station has reported 92.4 mm of rain 🌧️ pic.twitter.com/44ngvpLRi8

— NIWA Weather (@NiwaWeather) January 22, 2018

Floodwaters started to abate about an hour after the deluge began, but MetService warned it as just a foretaste of things to come today.

Forecaster Tom Adams said much of the North Island remained under a thunderstorm watch until at least 8pm.

He said similar super-sized downpours on localised areas were likely as there was little wind to move the storms away.

"There's not a lot of wind around so when a thunderstorm forms they will stay on one spot. The bad news is that there will be large amounts of rain over one spot."

He warned there was a risk of severe thunderstorms for the rest of the day.

"There are no other cells over the Auckland region but there's lots of opportunity for another two, three or four storms to pop up," said Adams.

One of those rescued this morning was Appar Singh, who was driving along Caribbean Dr when he suddenly hit the floodwaters.

His car became submerged and stopped.

"I tried to turn it on but it wasn't turning on," he said.

Singh was worried about the rising water level and called for help.

"My girlfriend was a bit scared but I tried to be brave," he said.

Appar Singh, far left, was trapped in his stalled car on Caribbean Drive. It and others caught in flash flooding will have to be towed. (Photo / Anna Leask)