Aucklanders are being warned to brace themselves for power cuts as strong winds, gale surges and localised tornadoes could hit the region today.
Vector has teams prepared to respond to possible outages and urging residents to prepare by charging up devices and phones and ensuring they have a working torch with spare batteries.
Residents are also advised to tie down any outdoor furniture, including barbecues that could be blown around by the strong winds.
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Vector head of network field services Marko Simunac said response teams were on standby but in some cases Vector may need to remotely shut down power to that area as a public safety precaution until crews arrive on site.
"We know it's the school holidays with lots of families at home and reliant on power for warmth and entertainment such as laptops. If the weather causes damage to power lines, we'll aim to restore power as quickly as possible while ensuring the safety of our crews and the public."
Simunac said there were some cases where it was unsafe for crews to begin working to fix outages, such as high winds.
People were also advised to stay well away from any damaged electrical equipment such as damaged power poles and report any issues to its outage centre on vector.co.nz/outages.
MetService shift meteorologist April Clark said there was a strong wind watch in place for not only Auckland, but also Great Barrier Island, Waikato, Coromandel, Eastern Bay of Plenty and Waitomo from between 9am and 9pm on Wednesday.
"From about mid-morning it's already going to be quite windy in the south-westerlies ... so that's the possibility winds could get to severe gale in exposed places as well."
Winds in exposed places in Auckland could reach up to 93km/h and some localised thunderstorms and lightning strikes were also likely.
"The whole day is just going to feel like a pretty stormy day for Auckland really and much of the country to be honest."
MetService has also issued a heavy snow watch for Clutha, Southland and lower Fiordland with snow expected to fall to 300 metres. About 8cm of snow is expected to fall to about 700m in Taihape from mid-afternoon.
How to prepare
• Stay away from fallen power lines or damaged electrical equipment.
• Watch out for falling tree branches as these can cause damage to power lines.
• Avoid possible damage to electrical appliances (in the unlikely event there is a power surge when the power is restored) by switching off appliances at the wall.
• Keep a torch and spare batteries handy and ensure that you have at least one telephone that does not rely on electricity for operation.
• Ensure that an alternate fuel is always available for cooking (e.g. gas for barbecue).
• If you have an electric garage door, prepare how you can gain entry to the garage another way so you have access to your vehicle.
• Tie down objects such as barbecues or trampolines that may be impacted by strong winds.
• If you are on tank water, please ensure you have plenty of bottled water available.