Hundreds of people are queuing at Wellington and Auckland airports to rebook flights after low cloud in the capital led to mass cancellations.
Wellington Airport said almost 100 flights and 6000 passengers were affected.
Wellington Airport external relations manager Phil Rennie said close to 100 flights had been cancelled today, while about 16 had been diverted.
"So it's been a pretty long and frustrating day for a lot of people here at the airport," he said.
"There's been a lot of people waiting here very frustrated, but also very patient they understand there's not a lot we can do about the weather."
He said airlines were warning passengers that it could take several days to clear the backlog because they were "pretty" booked up over the next few days.
The airport staff would be putting on some pizzas for those who were stranded at Wellington Airport for the night, he said.
"We don't think there'll be too many people that need to stay the night but if there are we will have blankets and pillows and food available for people."
He said the weather had been forecast to clear about midday but that did not happen. It was quite unusual since generally at this time of the year Wellington was very windy which meant that fog and low cloud did not stick around, he said.
People should keep checking with their airlines for the latest flight updates, he said.
One passenger, Jacqui Elmsly, who was returning home to Hamilton, said the weather could not be helped but she was annoyed at the queue jumpers who tried to push in to get their tickets sorted out.
"So if everyone could just be kind I wouldn't be this frustrated."
She said all the flights were full and she was not able to book anything until Thursday and planned to sleep at the airport until then.
Paul Brownd said he was frustrated and would probably have to spend the night at the airport since all the accommodation seemed to be booked out. But he said at least he had managed to book a flight to Auckland tomorrow morning.
Sally Ann Palmer was worried that she would not be able to get to Queenstown by tomorrow because she was going there to catch a flight to Brisbane to see her grandson.
Drizzle and foggy conditions this afternoon reduced visibility to 2km.
A spokesperson for Wellington Airport said larger jets had been unable to land for the past few hours, causing a slowdown in aircraft activity.
It is the third day in a row that passengers have faced disruption at Wellington Airport.
Air New Zealand chief integrity and safety officer Captain David Morgan said customers were being rebooked on the next available flights.
Due to limited availability, some people may not be able to travel for a day or two, he said.
Customers who no longer wish to travel or cannot find an alternative can get Air New Zealand credit for their cancelled airfare.
MetService said low cloud and drizzle in Wellington would continue to disrupt flights throughout the evening and possibly into early tomorrow morning.
Forecaster Gerard Bellam said although the low cloud may lift slightly tonight, visibility for pilots would still be poor.
"We are expecting that to lift a bit, there'll still be low cloud around but that should help with the aircraft operations, however there will be some drizzle at times, sort of patchy drizzle across Wellington so that can reduce the visibility."
MetService said visibility may reach up to 10km later on Tuesday evening but there would be periods where low cloud would return.
It said there was a small chance of seeing low cloud again on Wednesday morning.
