There are also reports of flooding in Christchurch and landslides in North Canterbury this afternoon. A slip on State Highway 35 at Cape Runaway, Bay of Plenty, has also resulted in the road being cut to one lane.
MetService said the storm “could be a significant weather event, with large amounts of rainfall expected between today and Friday” for the east of the South Island in particular.
MetService meteorologist Kgolofelo Dube said the heavy rain could mean further localised flooding, slips and poor driving conditions.
There is a moderate chance of thunderstorms for the upper North Island this afternoon including Northland, Auckland, Waikato and the Coromandel.
Severe wind gusts are also tipped to strike Auckland at rush hour tomorrow morning, with a heavy wind watch coming into force at 7am.
The New Zealand Transport Agency said the Auckland Harbour Bridge could see lane closures and speed reductions during the morning commute.
“We don’t take the decision to lower speeds, close lanes or close the bridge lightly. Our priority is the safety of road users and the bridge structure.
“Drivers of high sided vehicles and motorcyclists are advised to avoid the Auckland Harbour Bridge and use the western ring route on State Highways 16 and 18.”
‘Damaging’ 130km/h winds for Wellington, 10m swells cancel ferries
Cook Strait ferries have been cancelled until Saturday because of 10m swells caused by the severe winds.
A planned workers’ union rally for May Day in Wellington has also been cancelled due to the weather.
A strong wind warning will begin for coastal areas of Wairarapa at 9am and last 15 hours. In Wellington, the watch will begin at 3am and last for 21 hours.
MetService said the wind, an unusually strong southerly, threatened trees that were typically only at risk from northerlies.
“This means that trees ... may be more vulnerable ... making them more prone to damage.”
MetService has also issued the watch for Marlborough Sounds, Horowhenua and Kāpiti Coast, inland areas of Wairarapa, the Tararua District, and Hawke’s Bay south of Hastings tomorrow.
The New Zealand Transport Agency said SH35 at Cape Runaway could be shut if the slip there worsened.
The National Institute of Water and Atmospheric Research reported gusts may reach 120km/h in some places. MetService said winds could hit 130km/h.
Across the Cook Strait, the same watch will begin for Coastal Marlborough south of Blenheim, including the Kaikōura Coast, at 1am and last for 21 hours.
MetService is urging these communities to prepare for trees and powerlines to be damaged and to tie down any unsecured structures like trampolines.
“I can imagine that as well there’ll be some kind of transportation issues with those strong winds,” Dube said.
A strong wind watch will begin at 7am for Auckland, Great Barrier Island, Coromandel Peninsula, and Waikato north of Hamilton, with warnings the westerly winds may turn to severe gales in exposed areas.
Cantabrians told to brace for 40 hours of rain
Meanwhile, multiple regions in Canterbury were told to brace for close to 40 hours of rain, some even more.
State Highway 1 at Greta Valley in North Canterbury was blocked about 1.20pm today because of a slip near Stonyhurst Rd. The Christchurch City Council said roads were flooded in New Brighton and Wainoni.
A heavy rain warning was issued for the Kaikōura Coast and ranges, and for Canterbury about and north of Amberley, and between Amberley and Timaru, including Christchurch and Banks Peninsula, at 10am.
In Kaikōura, residents have been warned to expect between 180mm and 230mm of rain over 44 hours, those north of Amberley should expect from 160-210mm over 35 hours and 120-160mm is forecast for Christchurch and Banks Peninsula over 32 hours.
Along with the heavy rain, snow is also expected to fall as the wintry blast sends temperatures plummeting.
Dube said cold fronts passing over the country from the south were the driving force behind the dropping temperatures.
A heavy snow warning is in place for Canterbury high country south of the Rangitata River, with MetService telling residents to expect 12-20cm of snow to settle above 800m, with lesser amounts down to 700m.
A road snowfall warning will begin tonight for Arthur’s Pass (SH73), Porters Pass (SH73) and Lindis Pass (SH8) and tomorrow morning for Lewis Pass (SH7).
Between 3cm and 5cm of snow is expected to settle on the roads near the summit, with lesser amounts lower than 700m.
A heavy rain watch is in place for Bay of Plenty about and west of Ōpōtiki and Wairarapa.
The same warning will apply for Wellington tonight at 6pm and last for 45 hours.
