Thunderstorms, hail and strong wind gusts are forecast to bear down on the centre of the country and eastern parts of the South Island in the coming hours. 

Surface flooding is possible at the bottom of the North Island as a slow-moving weather system stalls over the region. 

The incoming rainmaker is also set to bring a cold snap to the country with snow falling on southern mountain passes, making driving treacherous. 

MetService today warned those living in Porirua, Lower Hutt and Upper Hutt and the Kāpiti Coast District residents to brace for downpours this evening. 

A heavy rain watch was due to come into effect at 8pm, with downpours of 25mm per hour likely until 8am Thursday. 

NIWA said wind gusts of more than 50km/h would also pummel the region this evening, increasing to 100km/h in the early hours of tomorrow morning. 

MetService meteorologist Ngaire Wotherspoon said the localised, heavy downpours were of particular concern due to the high risk of surface flooding. 

Wotherspoon said there was also a strong chance hail would fall in these areas along with strong wind gusts overnight. 

MetService meteorologist Lewis Ferris said the worst of the weather should occur while residents were inside their homes, but anyone driving after 8pm should take precautions. 

“The heaviest rain will be kind of gone by the time people are waking up tomorrow morning to get out and about,” Ferris said. 

“So if people are planning on putting their rubbish out tonight for collection tomorrow, I think it would be wiser to wait until the morning if possible.” 

Wotherspoon said the thunder and wet conditions would last until day-break with localised heavy rain and small hail expected over Marlborough Sounds, Wellington and southern Wairarapa. 

Ferris said there was potential for some “very strong winds” around the Taranaki region, getting up to 90km/h. 

A heavy rain warning is also in place for Canterbury north of Amberley, including the Kaikoura District, from 7pm until 5am. 

The surge of cooler temperatures will also see snow fall in alpine regions, falling as low as 900 metres. 

A road snowfall warning is in place for Lewis Pass (SH7) from 10pm until 3am, with 1cm of snow expected to blanket the roads near the summit. 

Ferris said the worst of the weather was expected to ease by tomorrow afternoon. 

“[There will be] lingering effects being felt around the centre of the country Thursday morning, but generally the weather is on an easing trend as we make our way towards Friday.” 

Rachel Maher is an Auckland-based reporter who covers breaking news. She has worked for the Herald since 2022. 

This article was originally published on the NZ Herald here.