The North Island is in for another stormy day with heavy rain and thunderstorms as former tropical cyclone Victor sweeps past the country.
MetService has issued a severe weather warning for Gisborne to east of Wairoa with up to 150mm predicted to fall in some areas over a 12-hour period.
The forecaster says Northland and northern parts of Auckland will be affected by unsettled showery southwesterlies with a low risk of one or two thunderstorms.
Those living on the east coast were being warned to watch out for quickly-rising streams and rivers, and to be aware of possible flash flooding and hazardous driving conditions.
The combination of humid subtropical air and wind convergences were also expected to trigger heavy showers over the upper half of the North Island, including Waitomo, Waikato, Taupo and Bay of Plenty.
Flooding: 'There's a lake at my doorstep'
Flash flooding hit parts of South Auckland last night as a slow-moving rainstorm passed over the area.
Rangitoto Rd resident Freda King said "two lakes" built up outside her Papatoetoe property.
"It was very worrying for a while," the 92-year-old said. "There were a lot of stones from the street blocking the drain, it seemed."
Andrew McLean said Ramsey St was completely underwater. "One of the houses on our street had water coming in the door.
"We had a bit of flooding in our garages, the road was all underwater, and it was running down our driveways."
Fenton St resident Amanda Chhour came home from work to find the rear of her property underwater and the creek near her house overflowing.
"It was pretty scary. You don't expect to see something like that in your backyard.
"Our neighbours can't get out of their driveway -- they're blocked in by the flooding."
A house in Ramsey St, Papatoetoe, reported water coming through the door, the police said.
Ian Wiley posted a photo of a fire engine responding to a call to a flooded basement in the suburb.
Another resident, Katie Nolan, posted on Facebook: "Did anyone see that rain? Woah!!!! My street is flooding."
Her message included the hashtag #Couldnotseeoutmywindow.
A post on the Papatoetoe Facebook page told residents of severe flooding around the suburb due to the deluge. "Please drive to the conditions. Eyes on the road!"
In an update shortly after 7pm, it said there was flooding on the Southern Motorway just before Te Irirangi Drive.
"Roads beginning to ease back to normal again. Drive to the conditions."
The Fire Service responded to more than 16 flood-related callouts within just over an hour from about 7pm last night.
Most of them were in the Papatoetoe, Mangere and Otahuhu areas.
"The majority of them were blocked drains [in the road and on people's property]," said spokeswoman Megan Ruru.
"There was one where a sewage system wasn't functioning correctly which had excrement [overflowing]. But we left that in the hands of Watercare."
It had been a busy hour and 15 minutes, Ms Ruru said, but "it seems to have stopped, fingers crossed".
WeatherWatch analyst Philip Duncan said his company received a photo of water being pumped out of a house in Clevedon.
"The downpours are as a result of humidity brought down by ex-Cyclone Victor combining with afternoon heat over land," he said.
"The light easterly wind in Auckland and Waikato today helped shift most of the risk into rural areas in the southwest of each region."
At the moment [7pm last night], we've still got a fair few thunderstorms around, they've moved sort of west of Taupo and west of Auckland and Northland, but those should be easing," MetService meteorologist Claire Flynn said.
A moderate thunderstorm risk was in place for eastern parts of Northland, Auckland and the Coromandel Peninsula on Thursday, she said. The Bay of Plenty, Taupo and east of Waikato were also at risk.
A heavy rain warning is in place for Gisborne for late Thursday morning and into the afternoon.
The upper North Island experienced some severe thunderstorms yesterday, as a result of the hot, humid air that has been lingering this week.
MetService reported more than 1000 lightning strikes across the island in the afternoon, and National Park received 66mm of rainfall in the 12 hours to 7pm.
Humid weather for the next 10 days
Very humid, very warm weather will hang around the North Island, according to weatherwatch.co.nz.
"The next 10 days have highs hovering around 27C and 30C, which may not sound overly hot to some people but with humidity between 60 and 90 per cent for much of this time the 'feels like' temperature will be around the low to mid 30s," WeatherWatch analyst Philip Duncan said.
"Overnight lows will be tough for sleeping, with temperatures hovering around 20C at the coldest time, and with humidity often closer to 100 per cent at night making it feel like the mid-to-late 20s for some."
Winds might provide welcome breaks from the humidity, he said.