Power cuts and damage are possible for the upper and western North Island from this evening, NIWA is warning.
MetService has issued strong weather warnings - Auckland, Coromandel Peninsula, Taranaki, and coastal Waikato will be worst affected.
Heavy winds, rain and possible thunderstorms are forecast for parts of the country into Wednesday.
And a NIWA spokesperson said winds of more than 100km/h were expected.
"The strongest gusts are likely over coastal & elevated areas," a post on X said.
"Localised power cuts and damage are possible."
After active weather tonight, wind gusts near or more than 100 km/h are expected from Taranaki to Waikato, Auckland, and Northland.
The strongest gusts are likely over coastal & elevated areas.
Localised power cuts & damage are possible.
100+ km/h pic.twitter.com/DCihiXis8e
— NIWA Weather (@NiwaWeather) May 27, 2024
Drivers using the Auckland Harbour Bridge tomorrow have also been asked to take xtra care.
NZ Transport Agency Waka Kotahi said it was likely speed limits would be reduced and some lanes could be closed if winds reached threshold levels.
With the strongest gusts forecast for midday and again from 6-7pm it was possible the bridge could be shut down completely temporarily, the trasnport agency said.
Drivers of high sided vehicles and motorcyclists were advised to avoid the bridge and use the western ring route on State Highways 16 and 18.
MetService has issued nine warnings or watches affecting Auckland and a part of Waikao in the north and extending as far south as Stewart Island.
Souwesters may hit gale levels in exposed places in parts of Auckland, including Great Barrier Island, from 4pm tomorrow.
MetService said on X gusts could reach 110km/h and might be accompanied by "gusty thunderstorms".
People were being advised to secure outdoor items such as wheelie bins and trampolines.
Heads up #Auckland, you're in for some wind tomorrow
Blustery southwesterlies are forecast to strengthen on Wednesday afternoon and gusts may reach 110km/h in the most exposed places before easing overnight
There is also a risk of gusty thunderstorms
Prepare ahead… pic.twitter.com/iL96DeqLbm
— MetService (@MetService) May 28, 2024
The strong wind watch also takes in the west coast of Waikato north of Kawhia Harbour, the Coromandel Peninsula and the Kaimai Range.
Western Taranaki from Urenui to Hawera may also be in for a similar dose of strong winds from 2pm tomorrow.
Heavy rain is forecast to move up the west coast of both islands also and reach Auckland and Northland later in the day.
There are snowfall warnings for three areas in the South Island also - Milford Road (SH94) from 10pm, Lindis Pass (SH8) and the Crown Range Road, both from 1am. Falls are expected to range from 1cm to 4cm.
Thunderstorms, strong winds and even some snow on the higher passes. The forecast for Wednesday is chock-a-block full of weather.https://t.co/NLcso2tdf2
— MetService (@MetService) May 28, 2024
Coastal parts of Clutha and Dunedin around the Otago Peninsula, coastal parts of Southland and Stewart Island are all expected to be affected by strong winds from around 8am.
Meanwhile, Christchurch had the chilliest start today at -3.3C.