Several regions were experiencing severe weather on Monday as a front crossed the country.
MetService says the front was passing over Nelson, Marlborough and Taranaki from the morning, bringing with it heavy rain.
It's warning people that rivers and streams will rise quickly.
Wellington and Wairarapa are also in for heavy weather, as north to northwest winds ahead of the front could reach gale force.
The winds are expected to die down by about 3pm on Monday.
Air New Zealand flights in and out of Wellington Airport were being delayed by up to 50 minutes due to the strong gusts.
Air New Zealand says 10 domestic morning flights had been affected, but was expecting to get back on schedule by early afternoon as the weather improves.
Snow showers in Te Anau could reach road level near the Milford Road tunnel until Monday afternoon