A severe thunderstorm watch has been issued for Northland from 7am tomorrow as wild weather that has battered parts of the South Island sweeps north.

NZ Transport Agency Waka Kotahi (NZTA) said drivers in Auckland should be prepared for the possibility of lane closures or reduced speeds on the bridge tomorrow morning.

Between 6am and 10am, wind gusts are forecast to hit 70-80km/h, with the potential to reach 90km/h.

These winds could trigger an amber alert, NZTA said.

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 as they head to work tomorrow.

The bridge would remain in a 4×4 configuration in the morning.

Closures or restrictions will be posted on NZTA social media channels.

Precautionary evacuation advised for Marlborough community

The Marlborough region is expecting significant rainfall, especially in the ranges.

An orange heavy rain warning was issued by MetService from 9am on Thursday to 6pm on Friday.

Mayor Nadine Taylor declared a local state of emergency for part of Marlborough this evening to facilitate the precautionary evacuation of Spring Creek.

The Wairau River stopbank at Spring Creek is currently in a compromised state, so Marlborough Emergency Management advised residents to plan to evacuate from 6am.

The streets affected by this precautionary evacuation in Spring Creek are Dodson, Hathaway and March Streets and part of Ferry Rd.

Marlborough Emergency Management controller Richard MacNamara said, “All of Marlborough’s emergency and lifelines agencies are up to speed, and our response teams are ready to go.”

Residents can leave this evening if they wish, but the key time when the river may be running high is from early tomorrow morning, MacNamara said.

Thunderstorms, strong winds and heavy rain

Before dawn, squally thunderstorms are expected to arrive in Northland. These thunderstorms will bring the risk of heavy downpours and strong wind gusts.

As the front moves across the island, the risk of thunderstorms spreads to other regions of the North Island and the top of the South Island.

MetService meteorologist Mmathapelo Makgabutlane told the Herald the upper North Island will receive short bursts of intense rain, which bring the potential for surface flooding.

“Auckland will see a short period of heavier rain as the main rain band moves through about lunchtime.”

This could peak at 27.7mm/h at noon in Auckland tomorrow.

Auckland is currently not under any watch or warning but Makgabutlane called it an “evolving situation”.

“We will be having a look at our latest information later this evening. Things could still change.”

The wild weather is likely to continue into the afternoon, with the worst of the rain forecast to pass by the evening, she said.

On Saturday the winds will shift southerly, directing heavy rain at Dunedin and Otago, with the possibility of heavy snow above 600m inland.

MetService meteorologist Michael Pawley said, “Sunday looks like the better day to travel if you’re going away for the school holidays because the severe weather is expected to ease.

“If you’re going skiing, I’d recommend staying cosy and dry while the fresh snow falls.”

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