All flights to and from Wellington tonight have been cancelled or diverted due to low fog.
Have your Christmas travel plans been affected? Contact our reporters.
Fog started to roll in from the south about 1pm and blanketed the city.
In a statement, Air New Zealand apologised for the inconvenience to passengers but said the fog at Wellington International Airport made it impossible to continue normal operations.
The airline said flights were expected to resume at 9am tomorrow and it was investigating adding additional capacity to accommodate disrupted passengers.
Brigitte Ransom, a spokeswoman for the airline, said the main problem was landing at the airport.
"The low cloud is causing problems and it's affecting the jets as well as the small planes. We are diverting flights to Nelson and Palmerston North and other flights have been cancelled."
Air New Zealand cancelled dozens of flights, while Jetstar cancelled 12, Radio New Zealand reported.
Virgin Australia also cancelled its international flights
Dunedin resident James Graham was due to fly to Wellington, but will now fly to Christchurch and then on to the capital at midday tomorrow.
He had arrived with his family at Dunedin Airport to "craziness" and huge lines.
The delay was annoying as his holiday would be cut a day short and he would miss out on time to do some last-minute Christmas shopping, he said.
Among those stranded at Wellington International Airport were the Central Coast Mariners football team, who played the Wellington Phoenix yesterday.
Team spokesman Ben O'Neill said the team had earlier been told they could hopefully fly out later tonight, but may have to wait until tomorrow.
Their next game was on Thursday and any delay could seriously impact on recovery plans, he said.
Several international Qantas flights are affected, with the airline also plagued by the breakdown of their computer system. Passengers were advised to call 0800 808 767 for information.
Australian resident Raewyn Anderson had been waiting to check in to her flight to Melbourne for two hours.
"We arrived before it (the fog) happened, it was just starting to come in when we got here.
"We didn't think anything of it, we thought there would be some system meaning we could still get out."
For up to date flight information visit www.wellingtonairport.co.nz.
- © Fairfax NZ News